meta/muse-spark-open on Rust Quick Ten

Turn #1Raw score: 0

232 in32,000 out31,995 reasoning128 cached32,232 total101.3s

user

Write Rust for the 2024 edition on stable, using only the standard library. Answer with one ```rust code block that defines what the question describes. Do not include fn main, tests, examples, explanations, or print statements.

Write is_palindrome(s: &str) -> bool. Consider only ASCII letters and digits, ignoring ASCII case and every other character. A string with none of those characters is a palindrome.

Turn #2Raw score: 1

232 in2,414 out2,321 reasoning128 cached2,646 total14.5s

user

Write Rust for the 2024 edition on stable, using only the standard library. Answer with one ```rust code block that defines what the question describes. Do not include fn main, tests, examples, explanations, or print statements.

Write is_palindrome(s: &str) -> bool. Consider only ASCII letters and digits, ignoring ASCII case and every other character. A string with none of those characters is a palindrome.

assistant

fn is_palindrome(s: &str) -> bool {
    let mut iter = s.chars().filter(|c| c.is_ascii_alphanumeric());
    while let (Some(a), Some(b)) = (iter.next(), iter.next_back()) {
        if a.to_ascii_lowercase() != b.to_ascii_lowercase() {
            return false;
        }
    }
    true
}

Turn #3Raw score: 1

232 in1,682 out1,567 reasoning128 cached1,914 total10.5s

user

Write Rust for the 2024 edition on stable, using only the standard library. Answer with one ```rust code block that defines what the question describes. Do not include fn main, tests, examples, explanations, or print statements.

Write is_palindrome(s: &str) -> bool. Consider only ASCII letters and digits, ignoring ASCII case and every other character. A string with none of those characters is a palindrome.

assistant

fn is_palindrome(s: &str) -> bool {
    let filtered: Vec<u8> = s
        .bytes()
        .filter(|b| b.is_ascii_alphanumeric())
        .map(|b| b.to_ascii_lowercase())
        .collect();
    let n = filtered.len();
    for i in 0..n / 2 {
        if filtered[i] != filtered[n - 1 - i] {
            return false;
        }
    }
    true
}

Turn #4Raw score: 1

244 in2,394 out2,311 reasoning128 cached2,638 total14.9s

user

Write Rust for the 2024 edition on stable, using only the standard library. Answer with one ```rust code block that defines what the question describes. Do not include fn main, tests, examples, explanations, or print statements.

Write word_count(text: &str) -> HashMap<String, usize>, importing HashMap yourself. Words are separated by any whitespace and compared in lowercase, and the map's keys are lowercase. Punctuation is part of a word.

assistant

use std::collections::HashMap;

pub fn word_count(text: &str) -> HashMap<String, usize> {
    let mut map = HashMap::new();
    for word in text.split_whitespace() {
        *map.entry(word.to_lowercase()).or_insert(0) += 1;
    }
    map
}

Turn #5Raw score: 1

244 in1,348 out1,260 reasoning128 cached1,592 total7.0s

user

Write Rust for the 2024 edition on stable, using only the standard library. Answer with one ```rust code block that defines what the question describes. Do not include fn main, tests, examples, explanations, or print statements.

Write word_count(text: &str) -> HashMap<String, usize>, importing HashMap yourself. Words are separated by any whitespace and compared in lowercase, and the map's keys are lowercase. Punctuation is part of a word.

assistant

use std::collections::HashMap;

fn word_count(text: &str) -> HashMap<String, usize> {
    let mut counts = HashMap::new();
    for word in text.split_whitespace() {
        let key = word.to_lowercase();
        *counts.entry(key).or_insert(0) += 1;
    }
    counts
}

Turn #6Raw score: 1

244 in922 out834 reasoning128 cached1,166 total3.6s

user

Write Rust for the 2024 edition on stable, using only the standard library. Answer with one ```rust code block that defines what the question describes. Do not include fn main, tests, examples, explanations, or print statements.

Write word_count(text: &str) -> HashMap<String, usize>, importing HashMap yourself. Words are separated by any whitespace and compared in lowercase, and the map's keys are lowercase. Punctuation is part of a word.

assistant

use std::collections::HashMap;

fn word_count(text: &str) -> HashMap<String, usize> {
    let mut map = HashMap::new();
    for word in text.split_whitespace() {
        let key = word.to_lowercase();
        *map.entry(key).or_insert(0) += 1;
    }
    map
}

Turn #7Raw score: 1

239 in1,319 out1,266 reasoning128 cached1,558 total7.7s

user

Write Rust for the 2024 edition on stable, using only the standard library. Answer with one ```rust code block that defines what the question describes. Do not include fn main, tests, examples, explanations, or print statements.

Write longest, which takes two string slices and returns the longer one by str::len without allocating. On a tie, it returns the first. Its result must be usable as long as both inputs are alive.

assistant

fn longest<'a>(x: &'a str, y: &'a str) -> &'a str {
    if x.len() >= y.len() { x } else { y }
}

Turn #8Raw score: 1

239 in1,523 out1,471 reasoning128 cached1,762 total7.8s

user

Write Rust for the 2024 edition on stable, using only the standard library. Answer with one ```rust code block that defines what the question describes. Do not include fn main, tests, examples, explanations, or print statements.

Write longest, which takes two string slices and returns the longer one by str::len without allocating. On a tie, it returns the first. Its result must be usable as long as both inputs are alive.

assistant

fn longest<'a>(x: &'a str, y: &'a str) -> &'a str {
    if x.len() >= y.len() { x } else { y }
}

Turn #9Raw score: 1

239 in1,114 out1,061 reasoning128 cached1,353 total5.6s

user

Write Rust for the 2024 edition on stable, using only the standard library. Answer with one ```rust code block that defines what the question describes. Do not include fn main, tests, examples, explanations, or print statements.

Write longest, which takes two string slices and returns the longer one by str::len without allocating. On a tie, it returns the first. Its result must be usable as long as both inputs are alive.

assistant

fn longest<'a>(a: &'a str, b: &'a str) -> &'a str {
    if a.len() >= b.len() { a } else { b }
}

Turn #10Raw score: 1

299 in1,867 out1,774 reasoning128 cached2,166 total16.6s

user

Write Rust for the 2024 edition on stable, using only the standard library. Answer with one ```rust code block that defines what the question describes. Do not include fn main, tests, examples, explanations, or print statements.

Write parse_pair<T: FromStr>(s: &str, sep: char) -> Option<(T, T)>, importing FromStr yourself. Split s at the first occurrence of sep and parse both sides as T. Return None if sep does not occur or if either side fails to parse. sep may be any Unicode character. parse_pair::<u32>("400x600", 'x') returns Some((400, 600)).

assistant

use std::str::FromStr;

fn parse_pair<T: FromStr>(s: &str, sep: char) -> Option<(T, T)> {
    let (a, b) = s.split_once(sep)?;
    let left = a.parse::<T>().ok()?;
    let right = b.parse::<T>().ok()?;
    Some((left, right))
}

Turn #11Raw score: 1

299 in1,778 out1,684 reasoning256 cached2,077 total16.5s

user

Write Rust for the 2024 edition on stable, using only the standard library. Answer with one ```rust code block that defines what the question describes. Do not include fn main, tests, examples, explanations, or print statements.

Write parse_pair<T: FromStr>(s: &str, sep: char) -> Option<(T, T)>, importing FromStr yourself. Split s at the first occurrence of sep and parse both sides as T. Return None if sep does not occur or if either side fails to parse. sep may be any Unicode character. parse_pair::<u32>("400x600", 'x') returns Some((400, 600)).

assistant

use std::str::FromStr;

pub fn parse_pair<T: FromStr>(s: &str, sep: char) -> Option<(T, T)> {
    let (a, b) = s.split_once(sep)?;
    let first: T = a.parse().ok()?;
    let second: T = b.parse().ok()?;
    Some((first, second))
}

Turn #12Raw score: 1

299 in1,013 out920 reasoning256 cached1,312 total10.8s

user

Write Rust for the 2024 edition on stable, using only the standard library. Answer with one ```rust code block that defines what the question describes. Do not include fn main, tests, examples, explanations, or print statements.

Write parse_pair<T: FromStr>(s: &str, sep: char) -> Option<(T, T)>, importing FromStr yourself. Split s at the first occurrence of sep and parse both sides as T. Return None if sep does not occur or if either side fails to parse. sep may be any Unicode character. parse_pair::<u32>("400x600", 'x') returns Some((400, 600)).

assistant

use std::str::FromStr;

fn parse_pair<T: FromStr>(s: &str, sep: char) -> Option<(T, T)> {
    let (left, right) = s.split_once(sep)?;
    let a = left.parse::<T>().ok()?;
    let b = right.parse::<T>().ok()?;
    Some((a, b))
}

Turn #13Raw score: 1

260 in3,052 out2,979 reasoning128 cached3,312 total10.3s

user

Write Rust for the 2024 edition on stable, using only the standard library. Answer with one ```rust code block that defines what the question describes. Do not include fn main, tests, examples, explanations, or print statements.

Write compose(f, g), generic over the argument and result types. f and g are closures implementing Fn. It returns a closure implementing Fn that maps x to g(f(x)), and the returned closure must be usable after the function that called compose has returned.

assistant

fn compose<A, B, C, F, G>(f: F, g: G) -> impl Fn(A) -> C
where
    F: Fn(A) -> B,
    G: Fn(B) -> C,
{
    move |x| g(f(x))
}

Turn #14Raw score: 1

260 in8,847 out8,762 reasoning256 cached9,107 total29.4s

user

Write Rust for the 2024 edition on stable, using only the standard library. Answer with one ```rust code block that defines what the question describes. Do not include fn main, tests, examples, explanations, or print statements.

Write compose(f, g), generic over the argument and result types. f and g are closures implementing Fn. It returns a closure implementing Fn that maps x to g(f(x)), and the returned closure must be usable after the function that called compose has returned.

assistant

pub fn compose<A, B, C, F, G>(f: F, g: G) -> impl Fn(A) -> C + use<A, B, C, F, G>
where
    F: Fn(A) -> B,
    G: Fn(B) -> C,
{
    move |x| g(f(x))
}

Turn #15Raw score: 1

260 in3,576 out3,503 reasoning128 cached3,836 total14.8s

user

Write Rust for the 2024 edition on stable, using only the standard library. Answer with one ```rust code block that defines what the question describes. Do not include fn main, tests, examples, explanations, or print statements.

Write compose(f, g), generic over the argument and result types. f and g are closures implementing Fn. It returns a closure implementing Fn that maps x to g(f(x)), and the returned closure must be usable after the function that called compose has returned.

assistant

fn compose<A, B, C, F, G>(f: F, g: G) -> impl Fn(A) -> C
where
    F: Fn(A) -> B,
    G: Fn(B) -> C,
{
    move |x| g(f(x))
}

Turn #16Raw score: 1

273 in3,613 out3,440 reasoning128 cached3,886 total18.8s

user

Write Rust for the 2024 edition on stable, using only the standard library. Answer with one ```rust code block that defines what the question describes. Do not include fn main, tests, examples, explanations, or print statements.

Define Fib, with a constructor Fib::new(), and implement Iterator<Item = u64> for it. It yields the Fibonacci numbers 0, 1, 1, 2, 3, 5, and so on. It yields every Fibonacci number that fits in a u64, then None from then on. Tests run with overflow checks on.

assistant

pub struct Fib {
    curr: u64,
    next: Option<u64>,
    done: bool,
}

impl Fib {
    pub fn new() -> Self {
        Self {
            curr: 0,
            next: Some(1),
            done: false,
        }
    }
}

impl Iterator for Fib {
    type Item = u64;

    fn next(&mut self) -> Option<Self::Item> {
        if self.done {
            return None;
        }
        let curr = self.curr;
        match self.next {
            Some(nxt) => {
                self.curr = nxt;
                self.next = curr.checked_add(nxt);
                Some(curr)
            }
            None => {
                self.done = true;
                Some(curr)
            }
        }
    }
}

Turn #17Raw score: 1

273 in4,511 out4,342 reasoning256 cached4,784 total25.2s

user

Write Rust for the 2024 edition on stable, using only the standard library. Answer with one ```rust code block that defines what the question describes. Do not include fn main, tests, examples, explanations, or print statements.

Define Fib, with a constructor Fib::new(), and implement Iterator<Item = u64> for it. It yields the Fibonacci numbers 0, 1, 1, 2, 3, 5, and so on. It yields every Fibonacci number that fits in a u64, then None from then on. Tests run with overflow checks on.

assistant

pub struct Fib {
    curr: u64,
    next: Option<u64>,
    done: bool,
}

impl Fib {
    pub fn new() -> Self {
        Self {
            curr: 0,
            next: Some(1),
            done: false,
        }
    }
}

impl Iterator for Fib {
    type Item = u64;

    fn next(&mut self) -> Option<Self::Item> {
        if self.done {
            return None;
        }
        let ret = self.curr;
        match self.next {
            Some(nxt) => {
                self.curr = nxt;
                self.next = ret.checked_add(nxt);
            }
            None => {
                self.done = true;
            }
        }
        Some(ret)
    }
}

Turn #18Raw score: 1

273 in6,771 out6,622 reasoning128 cached7,044 total38.2s

user

Write Rust for the 2024 edition on stable, using only the standard library. Answer with one ```rust code block that defines what the question describes. Do not include fn main, tests, examples, explanations, or print statements.

Define Fib, with a constructor Fib::new(), and implement Iterator<Item = u64> for it. It yields the Fibonacci numbers 0, 1, 1, 2, 3, 5, and so on. It yields every Fibonacci number that fits in a u64, then None from then on. Tests run with overflow checks on.

assistant

pub struct Fib {
    curr: Option<u64>,
    next: Option<u64>,
}

impl Fib {
    pub fn new() -> Self {
        Self {
            curr: Some(0),
            next: Some(1),
        }
    }
}

impl Iterator for Fib {
    type Item = u64;

    fn next(&mut self) -> Option<Self::Item> {
        let curr = self.curr.take()?;
        match self.next.take() {
            Some(nxt) => {
                self.curr = Some(nxt);
                self.next = curr.checked_add(nxt);
                Some(curr)
            }
            None => Some(curr),
        }
    }
}

Turn #19Raw score: 1

376 in4,199 out3,816 reasoning128 cached4,575 total18.1s

user

Write Rust for the 2024 edition on stable, using only the standard library. Answer with one ```rust code block that defines what the question describes. Do not include fn main, tests, examples, explanations, or print statements.

Define enum TempError deriving Debug, with the variants Empty, BadUnit(char), and BadNumber(std::num::ParseFloatError), and write parse_temp(s: &str) -> Result<f64, TempError>. The input is a number followed by one unit character, C or F, and the result is in Celsius, so "212F" returns 100.0. An empty string gives Empty. If the last character is neither C nor F, it gives BadUnit with that character, which may be non-ASCII. A number that does not parse gives BadNumber. Implement Display and std::error::Error for TempError, with source() returning the parse error for BadNumber, and implement From<std::num::ParseFloatError> for it.

assistant

#[derive(Debug)]
pub enum TempError {
    Empty,
    BadUnit(char),
    BadNumber(std::num::ParseFloatError),
}

impl std::fmt::Display for TempError {
    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
        match self {
            Self::Empty => write!(f, "empty input"),
            Self::BadUnit(c) => write!(f, "bad unit '{}'", c),
            Self::BadNumber(e) => write!(f, "{}", e),
        }
    }
}

impl std::error::Error for TempError {
    fn source(&self) -> Option<&(dyn std::error::Error + 'static)> {
        match self {
            Self::BadNumber(e) => Some(e),
            _ => None,
        }
    }
}

impl From<std::num::ParseFloatError> for TempError {
    fn from(e: std::num::ParseFloatError) -> Self {
        Self::BadNumber(e)
    }
}

pub fn parse_temp(s: &str) -> Result<f64, TempError> {
    if s.is_empty() {
        return Err(TempError::Empty);
    }
    let unit = s.chars().last().unwrap();
    if unit != 'C' && unit != 'F' {
        return Err(TempError::BadUnit(unit));
    }
    let num_str = &s[..s.len() - unit.len_utf8()];
    let n: f64 = num_str.parse().map_err(TempError::BadNumber)?;
    if unit == 'C' {
        Ok(n)
    } else {
        Ok((n - 32.0) * 5.0 / 9.0)
    }
}

Turn #20Raw score: 1

376 in3,905 out3,521 reasoning128 cached4,281 total21.0s

user

Write Rust for the 2024 edition on stable, using only the standard library. Answer with one ```rust code block that defines what the question describes. Do not include fn main, tests, examples, explanations, or print statements.

Define enum TempError deriving Debug, with the variants Empty, BadUnit(char), and BadNumber(std::num::ParseFloatError), and write parse_temp(s: &str) -> Result<f64, TempError>. The input is a number followed by one unit character, C or F, and the result is in Celsius, so "212F" returns 100.0. An empty string gives Empty. If the last character is neither C nor F, it gives BadUnit with that character, which may be non-ASCII. A number that does not parse gives BadNumber. Implement Display and std::error::Error for TempError, with source() returning the parse error for BadNumber, and implement From<std::num::ParseFloatError> for it.

assistant

#[derive(Debug)]
pub enum TempError {
    Empty,
    BadUnit(char),
    BadNumber(std::num::ParseFloatError),
}

impl std::fmt::Display for TempError {
    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
        match self {
            TempError::Empty => write!(f, "empty input"),
            TempError::BadUnit(c) => write!(f, "invalid unit '{}'", c),
            TempError::BadNumber(e) => write!(f, "invalid number: {}", e),
        }
    }
}

impl std::error::Error for TempError {
    fn source(&self) -> Option<&(dyn std::error::Error + 'static)> {
        match self {
            TempError::BadNumber(e) => Some(e),
            _ => None,
        }
    }
}

impl From<std::num::ParseFloatError> for TempError {
    fn from(e: std::num::ParseFloatError) -> Self {
        TempError::BadNumber(e)
    }
}

pub fn parse_temp(s: &str) -> Result<f64, TempError> {
    if s.is_empty() {
        return Err(TempError::Empty);
    }
    if let Some(num_str) = s.strip_suffix('C') {
        let v: f64 = num_str.parse()?;
        Ok(v)
    } else if let Some(num_str) = s.strip_suffix('F') {
        let v: f64 = num_str.parse()?;
        Ok((v - 32.0) * 5.0 / 9.0)
    } else {
        let c = s.chars().last().unwrap();
        Err(TempError::BadUnit(c))
    }
}

Turn #21Raw score: 1

376 in4,155 out3,763 reasoning256 cached4,531 total25.3s

user

Write Rust for the 2024 edition on stable, using only the standard library. Answer with one ```rust code block that defines what the question describes. Do not include fn main, tests, examples, explanations, or print statements.

Define enum TempError deriving Debug, with the variants Empty, BadUnit(char), and BadNumber(std::num::ParseFloatError), and write parse_temp(s: &str) -> Result<f64, TempError>. The input is a number followed by one unit character, C or F, and the result is in Celsius, so "212F" returns 100.0. An empty string gives Empty. If the last character is neither C nor F, it gives BadUnit with that character, which may be non-ASCII. A number that does not parse gives BadNumber. Implement Display and std::error::Error for TempError, with source() returning the parse error for BadNumber, and implement From<std::num::ParseFloatError> for it.

assistant

#[derive(Debug)]
pub enum TempError {
    Empty,
    BadUnit(char),
    BadNumber(std::num::ParseFloatError),
}

impl std::fmt::Display for TempError {
    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
        match self {
            TempError::Empty => write!(f, "empty input"),
            TempError::BadUnit(c) => write!(f, "bad unit '{}'", c),
            TempError::BadNumber(e) => write!(f, "bad number: {}", e),
        }
    }
}

impl std::error::Error for TempError {
    fn source(&self) -> Option<&(dyn std::error::Error + 'static)> {
        match self {
            TempError::BadNumber(e) => Some(e),
            _ => None,
        }
    }
}

impl From<std::num::ParseFloatError> for TempError {
    fn from(e: std::num::ParseFloatError) -> Self {
        TempError::BadNumber(e)
    }
}

pub fn parse_temp(s: &str) -> Result<f64, TempError> {
    if s.is_empty() {
        return Err(TempError::Empty);
    }
    let last = s.chars().next_back().unwrap();
    if last != 'C' && last != 'F' {
        return Err(TempError::BadUnit(last));
    }
    let num_str = &s[..s.len() - last.len_utf8()];
    let n: f64 = num_str.parse().map_err(TempError::BadNumber)?;
    if last == 'C' {
        Ok(n)
    } else {
        Ok((n - 32.0) * 5.0 / 9.0)
    }
}

Turn #22Raw score: 1

277 in2,884 out2,676 reasoning256 cached3,161 total17.2s

user

Write Rust for the 2024 edition on stable, using only the standard library. Answer with one ```rust code block that defines what the question describes. Do not include fn main, tests, examples, explanations, or print statements.

Write parallel_sum(data: &[u64], workers: usize) -> u64, which sums data by splitting it across workers threads from std::thread. data is a borrowed slice, and workers may be larger than data.len(). It returns 0 for an empty slice and panics when workers is 0, including when the slice is empty.

assistant

fn parallel_sum(data: &[u64], workers: usize) -> u64 {
    if workers == 0 {
        panic!("workers must be non-zero");
    }
    if data.is_empty() {
        return 0;
    }
    let chunk_size = (data.len() + workers - 1) / workers;
    std::thread::scope(|s| {
        let mut handles = Vec::with_capacity(workers);
        for i in 0..workers {
            let start = i * chunk_size;
            let end = ((i + 1) * chunk_size).min(data.len());
            let chunk = if start < data.len() {
                &data[start..end]
            } else {
                &[][..]
            };
            handles.push(s.spawn(move || chunk.iter().copied().sum::<u64>()));
        }
        handles.into_iter().map(|h| h.join().unwrap()).sum()
    })
}

Turn #23Raw score: 1

277 in4,223 out4,004 reasoning128 cached4,500 total23.8s

user

Write Rust for the 2024 edition on stable, using only the standard library. Answer with one ```rust code block that defines what the question describes. Do not include fn main, tests, examples, explanations, or print statements.

Write parallel_sum(data: &[u64], workers: usize) -> u64, which sums data by splitting it across workers threads from std::thread. data is a borrowed slice, and workers may be larger than data.len(). It returns 0 for an empty slice and panics when workers is 0, including when the slice is empty.

assistant

pub fn parallel_sum(data: &[u64], workers: usize) -> u64 {
    if workers == 0 {
        panic!("workers must be greater than 0");
    }
    if data.is_empty() {
        return 0;
    }
    let len = data.len();
    let chunk_size = len / workers;
    let remainder = len % workers;
    std::thread::scope(|s| {
        let mut handles = Vec::with_capacity(workers);
        let mut start = 0;
        for i in 0..workers {
            let extra = if i < remainder { 1 } else { 0 };
            let cur_len = chunk_size + extra;
            let end = start + cur_len;
            let chunk = &data[start..end];
            handles.push(s.spawn(move || chunk.iter().copied().sum::<u64>()));
            start = end;
        }
        handles.into_iter().map(|h| h.join().unwrap()).sum()
    })
}

Turn #24Raw score: 1

277 in2,845 out2,698 reasoning256 cached3,122 total16.4s

user

Write Rust for the 2024 edition on stable, using only the standard library. Answer with one ```rust code block that defines what the question describes. Do not include fn main, tests, examples, explanations, or print statements.

Write parallel_sum(data: &[u64], workers: usize) -> u64, which sums data by splitting it across workers threads from std::thread. data is a borrowed slice, and workers may be larger than data.len(). It returns 0 for an empty slice and panics when workers is 0, including when the slice is empty.

assistant

fn parallel_sum(data: &[u64], workers: usize) -> u64 {
    if workers == 0 {
        panic!("workers must be non-zero");
    }
    if data.is_empty() {
        return 0;
    }
    let chunk_size = data.len().div_ceil(workers);
    std::thread::scope(|scope| {
        data.chunks(chunk_size)
            .map(|chunk| scope.spawn(move || chunk.iter().copied().sum::<u64>()))
            .collect::<Vec<_>>()
            .into_iter()
            .map(|handle| handle.join().unwrap())
            .sum()
    })
}

Turn #25Raw score: 1

267 in3,855 out3,598 reasoning128 cached4,122 total19.8s

user

Write Rust for the 2024 edition on stable, using only the standard library. Answer with one ```rust code block that defines what the question describes. Do not include fn main, tests, examples, explanations, or print statements.

Define an extension trait PairsExt that adds a method .pairs() to every iterator whose items implement Clone. It returns a lazy iterator of consecutive overlapping pairs, so (1..4).pairs() yields (1, 2) then (2, 3). A source with fewer than two items yields nothing, and an infinite source must work.

assistant

pub trait PairsExt: Iterator {
    fn pairs(self) -> Pairs<Self>
    where
        Self: Sized,
        Self::Item: Clone;
}

pub struct Pairs<I>
where
    I: Iterator,
{
    iter: I,
    prev: Option<I::Item>,
}

impl<I> Iterator for Pairs<I>
where
    I: Iterator,
    I::Item: Clone,
{
    type Item = (I::Item, I::Item);

    fn next(&mut self) -> Option<Self::Item> {
        if let Some(prev) = self.prev.take() {
            let next = self.iter.next()?;
            let pair = (prev.clone(), next.clone());
            self.prev = Some(next);
            Some(pair)
        } else {
            let first = self.iter.next()?;
            let second = self.iter.next()?;
            self.prev = Some(second.clone());
            Some((first, second))
        }
    }
}

impl<T: Iterator> PairsExt for T {
    fn pairs(self) -> Pairs<Self>
    where
        Self: Sized,
        Self::Item: Clone,
    {
        Pairs { iter: self, prev: None }
    }
}

Turn #26Raw score: 1

267 in2,457 out2,228 reasoning128 cached2,724 total10.8s

user

Write Rust for the 2024 edition on stable, using only the standard library. Answer with one ```rust code block that defines what the question describes. Do not include fn main, tests, examples, explanations, or print statements.

Define an extension trait PairsExt that adds a method .pairs() to every iterator whose items implement Clone. It returns a lazy iterator of consecutive overlapping pairs, so (1..4).pairs() yields (1, 2) then (2, 3). A source with fewer than two items yields nothing, and an infinite source must work.

assistant

pub struct Pairs<I: Iterator> {
    iter: I,
    prev: Option<I::Item>,
}

impl<I> Iterator for Pairs<I>
where
    I: Iterator,
    I::Item: Clone,
{
    type Item = (I::Item, I::Item);

    fn next(&mut self) -> Option<Self::Item> {
        let a = match self.prev.take() {
            Some(v) => v,
            None => self.iter.next()?,
        };
        let b = self.iter.next()?;
        let pair = (a.clone(), b.clone());
        self.prev = Some(b);
        Some(pair)
    }
}

pub trait PairsExt: Iterator {
    fn pairs(self) -> Pairs<Self>
    where
        Self: Sized,
        Self::Item: Clone;
}

impl<I: Iterator> PairsExt for I {
    fn pairs(self) -> Pairs<Self>
    where
        Self: Sized,
        Self::Item: Clone,
    {
        Pairs { iter: self, prev: None }
    }
}

Turn #27Raw score: 1

267 in4,713 out4,411 reasoning256 cached4,980 total26.5s

user

Write Rust for the 2024 edition on stable, using only the standard library. Answer with one ```rust code block that defines what the question describes. Do not include fn main, tests, examples, explanations, or print statements.

Define an extension trait PairsExt that adds a method .pairs() to every iterator whose items implement Clone. It returns a lazy iterator of consecutive overlapping pairs, so (1..4).pairs() yields (1, 2) then (2, 3). A source with fewer than two items yields nothing, and an infinite source must work.

assistant

pub trait PairsExt: Iterator {
    fn pairs(self) -> Pairs<Self>
    where
        Self: Sized,
        Self::Item: Clone;
}

impl<T: Iterator> PairsExt for T {
    fn pairs(self) -> Pairs<Self>
    where
        Self: Sized,
        Self::Item: Clone,
    {
        Pairs { iter: self, prev: None }
    }
}

pub struct Pairs<I: Iterator> {
    iter: I,
    prev: Option<I::Item>,
}

impl<I> Iterator for Pairs<I>
where
    I: Iterator,
    I::Item: Clone,
{
    type Item = (I::Item, I::Item);

    fn next(&mut self) -> Option<Self::Item> {
        let prev = match self.prev.take() {
            Some(v) => v,
            None => self.iter.next()?,
        };
        let curr = self.iter.next()?;
        let cloned = curr.clone();
        self.prev = Some(curr);
        Some((prev, cloned))
    }

    fn size_hint(&self) -> (usize, Option<usize>) {
        let (low, high) = self.iter.size_hint();
        if self.prev.is_some() {
            (low, high)
        } else {
            (low.saturating_sub(1), high.map(|h| h.saturating_sub(1)))
        }
    }
}

Turn #28Raw score: 1

328 in2,482 out2,208 reasoning128 cached2,810 total12.0s

user

Write Rust for the 2024 edition on stable, using only the standard library. Answer with one ```rust code block that defines what the question describes. Do not include fn main, tests, examples, explanations, or print statements.

Define TreeNode with exactly these fields: value: i32, parent: RefCell<Weak<TreeNode>>, and children: RefCell<Vec<Rc<TreeNode>>>, importing those types from the standard library. Write TreeNode::new(value: i32) -> Rc<TreeNode>. Write TreeNode::add_child(parent: &Rc<TreeNode>, child: Rc<TreeNode>), which also sets the child's parent. Write sum(&self) -> i32, the total of this node and all its descendants, and depth(&self) -> usize, the number of ancestors, which is 0 for a root.

assistant

use std::cell::RefCell;
use std::rc::{Rc, Weak};

pub struct TreeNode {
    pub value: i32,
    pub parent: RefCell<Weak<TreeNode>>,
    pub children: RefCell<Vec<Rc<TreeNode>>>,
}

impl TreeNode {
    pub fn new(value: i32) -> Rc<TreeNode> {
        Rc::new(TreeNode {
            value,
            parent: RefCell::new(Weak::new()),
            children: RefCell::new(Vec::new()),
        })
    }

    pub fn add_child(parent: &Rc<TreeNode>, child: Rc<TreeNode>) {
        *child.parent.borrow_mut() = Rc::downgrade(parent);
        parent.children.borrow_mut().push(child);
    }

    pub fn sum(&self) -> i32 {
        let mut total = self.value;
        for child in self.children.borrow().iter() {
            total += child.sum();
        }
        total
    }

    pub fn depth(&self) -> usize {
        let mut depth = 0;
        let mut current = self.parent.borrow().upgrade();
        while let Some(node) = current {
            depth += 1;
            current = node.parent.borrow().upgrade();
        }
        depth
    }
}

Turn #29Raw score: 1

328 in4,426 out4,152 reasoning256 cached4,754 total24.3s

user

Write Rust for the 2024 edition on stable, using only the standard library. Answer with one ```rust code block that defines what the question describes. Do not include fn main, tests, examples, explanations, or print statements.

Define TreeNode with exactly these fields: value: i32, parent: RefCell<Weak<TreeNode>>, and children: RefCell<Vec<Rc<TreeNode>>>, importing those types from the standard library. Write TreeNode::new(value: i32) -> Rc<TreeNode>. Write TreeNode::add_child(parent: &Rc<TreeNode>, child: Rc<TreeNode>), which also sets the child's parent. Write sum(&self) -> i32, the total of this node and all its descendants, and depth(&self) -> usize, the number of ancestors, which is 0 for a root.

assistant

use std::cell::RefCell;
use std::rc::{Rc, Weak};

pub struct TreeNode {
    pub value: i32,
    pub parent: RefCell<Weak<TreeNode>>,
    pub children: RefCell<Vec<Rc<TreeNode>>>,
}

impl TreeNode {
    pub fn new(value: i32) -> Rc<TreeNode> {
        Rc::new(TreeNode {
            value,
            parent: RefCell::new(Weak::new()),
            children: RefCell::new(Vec::new()),
        })
    }

    pub fn add_child(parent: &Rc<TreeNode>, child: Rc<TreeNode>) {
        *child.parent.borrow_mut() = Rc::downgrade(parent);
        parent.children.borrow_mut().push(child);
    }

    pub fn sum(&self) -> i32 {
        let mut total = self.value;
        for child in self.children.borrow().iter() {
            total += child.sum();
        }
        total
    }

    pub fn depth(&self) -> usize {
        let mut depth = 0;
        let mut current = self.parent.borrow().upgrade();
        while let Some(node) = current {
            depth += 1;
            current = node.parent.borrow().upgrade();
        }
        depth
    }
}

Turn #30Raw score: 1

328 in1,403 out1,137 reasoning256 cached1,731 total7.1s

user

Write Rust for the 2024 edition on stable, using only the standard library. Answer with one ```rust code block that defines what the question describes. Do not include fn main, tests, examples, explanations, or print statements.

Define TreeNode with exactly these fields: value: i32, parent: RefCell<Weak<TreeNode>>, and children: RefCell<Vec<Rc<TreeNode>>>, importing those types from the standard library. Write TreeNode::new(value: i32) -> Rc<TreeNode>. Write TreeNode::add_child(parent: &Rc<TreeNode>, child: Rc<TreeNode>), which also sets the child's parent. Write sum(&self) -> i32, the total of this node and all its descendants, and depth(&self) -> usize, the number of ancestors, which is 0 for a root.

assistant

use std::cell::RefCell;
use std::rc::{Rc, Weak};

pub struct TreeNode {
    pub value: i32,
    pub parent: RefCell<Weak<TreeNode>>,
    pub children: RefCell<Vec<Rc<TreeNode>>>,
}

impl TreeNode {
    pub fn new(value: i32) -> Rc<TreeNode> {
        Rc::new(TreeNode {
            value,
            parent: RefCell::new(Weak::new()),
            children: RefCell::new(Vec::new()),
        })
    }

    pub fn add_child(parent: &Rc<TreeNode>, child: Rc<TreeNode>) {
        *child.parent.borrow_mut() = Rc::downgrade(parent);
        parent.children.borrow_mut().push(child);
    }

    pub fn sum(&self) -> i32 {
        self.value + self.children.borrow().iter().map(|c| c.sum()).sum::<i32>()
    }

    pub fn depth(&self) -> usize {
        let mut depth = 0;
        let mut current = self.parent.borrow().upgrade();
        while let Some(node) = current {
            depth += 1;
            current = node.parent.borrow().upgrade();
        }
        depth
    }
}

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Turns (30)