nvidia/nemotron-3-ultra-550b-a55b:free on Rust Quick Ten

Turn #1Raw score: 1

107 in680 out602 reasoning787 total19.1s

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.

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

pub fn is_palindrome(s: &str) -> bool {
    let filtered: Vec<char> = s
        .chars()
        .filter(|c| c.is_ascii_alphanumeric())
        .map(|c| c.to_ascii_lowercase())
        .collect();

    filtered.iter().eq(filtered.iter().rev())
}

Turn #2Raw score: 1

107 in520 out442 reasoning627 total17.3s

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.

assistant

pub fn is_palindrome(s: &str) -> bool {
    let filtered: Vec<char> = s
        .chars()
        .filter(|c| c.is_ascii_alphanumeric())
        .map(|c| c.to_ascii_lowercase())
        .collect();
    filtered.iter().eq(filtered.iter().rev())
}

Turn #3Raw score: 1

107 in819 out741 reasoning926 total46.6s

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 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

pub fn is_palindrome(s: &str) -> bool {
    let filtered: Vec<char> = s
        .chars()
        .filter(|c| c.is_ascii_alphanumeric())
        .map(|c| c.to_ascii_lowercase())
        .collect();

    filtered.iter().eq(filtered.iter().rev())
}

Turn #4Raw score: 1

118 in359 out283 reasoning477 total7.5s

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 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() {
        *counts.entry(word.to_lowercase()).or_insert(0) += 1;
    }
    counts
}

Turn #5Raw score: 1

118 in327 out251 reasoning445 total4.2s

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 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() {
        *counts.entry(word.to_lowercase()).or_insert(0) += 1;
    }
    counts
}

Turn #6Raw score: 1

118 in375 out298 reasoning493 total42.2s

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 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 counts = HashMap::new();
    for word in text.split_whitespace() {
        *counts.entry(word.to_lowercase()).or_insert(0) += 1;
    }
    counts
}

Turn #7Raw score: 1

112 in332 out281 reasoning444 total8.5s

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 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 #8Raw score: 1

112 in316 out259 reasoning428 total6.0s

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 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>(s1: &'a str, s2: &'a str) -> &'a str {
    if s1.len() >= s2.len() {
        s1
    } else {
        s2
    }
}

Turn #9Raw score: 1

112 in343 out286 reasoning455 total22.4s

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 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>(s1: &'a str, s2: &'a str) -> &'a str {
    if s1.len() >= s2.len() {
        s1
    } else {
        s2
    }
}

Turn #10Raw score: 1

181 in638 out568 reasoning819 total19.6s

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 (left, right) = s.split_once(sep)?;
    Some((left.parse().ok()?, right.parse().ok()?))
}

Turn #11Raw score: 1

181 in230 out149 reasoning411 total6.6s

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 (left, right) = s.split_once(sep)?;
    let left = left.parse().ok()?;
    let right = right.parse().ok()?;
    Some((left, right))
}

Turn #12Raw score: 1

181 in436 out351 reasoning617 total44.4s

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 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 left = left.parse::<T>().ok()?;
    let right = right.parse::<T>().ok()?;
    Some((left, right))
}

Turn #13Raw score: 1

135 in1,197 out1,131 reasoning1,332 total73.9s

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 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<F, G, A, B, C>(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

135 in465 out400 reasoning600 total10.6s

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 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 #15Raw score: 1

135 in507 out441 reasoning642 total13.5s

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 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<F, G, T, U, V>(f: F, g: G) -> impl Fn(T) -> V
where
    F: Fn(T) -> U,
    G: Fn(U) -> V,
{
    move |x| g(f(x))
}

Turn #16Raw score: 0

151 in277 out168 reasoning428 total13.2s

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

struct Fib {
    current: u64,
    next: u64,
}

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

impl Iterator for Fib {
    type Item = u64;

    fn next(&mut self) -> Option<Self::Item> {
        let current = self.current;
        self.current = self.next;
        self.next = self.next.checked_add(current)?;
        Some(current)
    }
}

Turn #17Raw score: 1

151 in6,597 out6,428 reasoning6,748 total201.2s

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 curr = self.curr;
        match self.next {
            Some(next) => {
                self.curr = next;
                self.next = curr.checked_add(next);
                Some(curr)
            }
            None => {
                self.done = true;
                Some(curr)
            }
        }
    }
}

Turn #18Raw score: 1

151 in6,794 out6,629 reasoning6,945 total247.2s

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

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

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

impl Iterator for Fib {
    type Item = u64;

    fn next(&mut self) -> Option<Self::Item> {
        if self.next.is_none() && self.curr == 0 {
            return None;
        }

        let res = self.curr;

        match self.next {
            Some(n) => {
                self.curr = n;
                self.next = res.checked_add(n);
            }
            None => {
                self.curr = 0;
            }
        }

        Some(res)
    }
}

Turn #19Raw score: 1

254 in786 out377 reasoning1,040 total23.1s

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

use std::error::Error;
use std::fmt;
use std::num::ParseFloatError;

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

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

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

fn parse_temp(s: &str) -> Result<f64, TempError> {
    if s.is_empty() {
        return Err(TempError::Empty);
    }

    let mut chars = s.chars();
    let unit = chars.next_back().ok_or(TempError::Empty)?;
    let number_str: String = chars.collect();

    if number_str.is_empty() {
        return Err(TempError::BadNumber(number_str.parse::<f64>().unwrap_err()));
    }

    let value: f64 = number_str.parse()?;

    match unit {
        'C' | 'c' => Ok(value),
        'F' | 'f' => Ok((value - 32.0) * 5.0 / 9.0),
        _ => Err(TempError::BadUnit(unit)),
    }
}

Turn #20Raw score: 1

254 in1,122 out754 reasoning1,376 total34.6s

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.

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

use std::error::Error;
use std::fmt;
use std::num::ParseFloatError;

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

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

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

fn parse_temp(s: &str) -> Result<f64, TempError> {
    if s.is_empty() {
        return Err(TempError::Empty);
    }

    let unit = s.chars().last().unwrap();
    let num_str = &s[..s.len() - unit.len_utf8()];

    let value: f64 = num_str.parse()?;

    match unit {
        'C' => Ok(value),
        'F' => Ok((value - 32.0) * 5.0 / 9.0),
        _ => Err(TempError::BadUnit(unit)),
    }
}

Turn #21Raw score: 1

254 in1,432 out1,029 reasoning1,686 total32.9s

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.

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

use std::error::Error;
use std::fmt;
use std::num::ParseFloatError;

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

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

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

fn parse_temp(s: &str) -> Result<f64, TempError> {
    if s.is_empty() {
        return Err(TempError::Empty);
    }

    let last_char = s.chars().last().unwrap();
    let number_part = &s[..s.len() - last_char.len_utf8()];

    if last_char != 'C' && last_char != 'F' {
        return Err(TempError::BadUnit(last_char));
    }

    let value: f64 = number_part.parse()?;

    let celsius = match last_char {
        'C' => value,
        'F' => (value - 32.0) * 5.0 / 9.0,
        _ => unreachable!(),
    };

    Ok(celsius)
}

Turn #22Raw score: 1

155 in1,346 out1,174 reasoning1,501 total45.8s

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

use std::thread;

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 workers = workers.min(data.len());
    let chunk_size = (data.len() + workers - 1) / workers;

    thread::scope(|s| {
        let mut handles = Vec::with_capacity(workers);

        for chunk in data.chunks(chunk_size) {
            let handle = s.spawn(move || chunk.iter().sum::<u64>());
            handles.push(handle);
        }

        handles.into_iter().map(|h| h.join().unwrap()).sum()
    })
}

Turn #23Raw score: 1

155 in2,235 out2,076 reasoning2,390 total84.4s

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

use std::thread;

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 chunk_size = data.len().div_ceil(workers);
    let mut handles = Vec::with_capacity(workers);

    for chunk in data.chunks(chunk_size) {
        let chunk = chunk.to_vec();
        let handle = thread::spawn(move || chunk.iter().sum::<u64>());
        handles.push(handle);
    }

    handles.into_iter().map(|h| h.join().unwrap()).sum()
}

Turn #24Raw score: 1

155 in898 out729 reasoning1,053 total22.0s

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 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

use std::thread;

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 chunk_size = (data.len() + workers - 1) / workers;

    thread::scope(|s| {
        let mut handles = Vec::with_capacity(workers.min(data.len()));

        for chunk in data.chunks(chunk_size) {
            let handle = s.spawn(move || chunk.iter().copied().sum::<u64>());
            handles.push(handle);
        }

        handles.into_iter().map(|h| h.join().unwrap()).sum()
    })
}

Turn #25Raw score: 0

141 in1,173 out952 reasoning1,314 total30.7s

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.

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,
    {
        Pairs::new(self)
    }
}

impl<I: Iterator> PairsExt for I {}

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

impl<I> Pairs<I>
where
    I: Iterator,
    I::Item: Clone,
{
    fn new(iter: I) -> Self {
        Self { iter, prev: None }
    }
}

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> {
        loop {
            let current = self.iter.next()?;
            if let Some(prev) = self.prev.replace(current.clone()) {
                return Some((prev, current));
            }
        }
    }
}

Turn #26Raw score: 0

141 in2,126 out1,942 reasoning2,267 total68.5s

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;
}

pub struct Pairs<I> {
    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 current = self.iter.next()?;
        if let Some(prev) = self.prev.take() {
            self.prev = Some(current.clone());
            Some((prev, current))
        } else {
            self.prev = Some(current);
            self.next()
        }
    }
}

impl<I> PairsExt for I where I: Iterator {}

Turn #27Raw score: 0

141 in2,523 out2,324 reasoning2,664 total55.2s

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 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

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

impl<I: Iterator> PairsExt for I {}

struct Pairs<I> {
    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 self.prev.is_none() {
            self.prev = self.iter.next();
        }
        let prev = self.prev.take()?;
        let current = self.iter.next()?;
        self.prev = Some(current.clone());
        Some((prev, current))
    }
}

Turn #28Raw score: 1

215 in887 out590 reasoning1,102 total26.3s

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<Self> {
        Rc::new(TreeNode {
            value,
            parent: RefCell::new(Weak::new()),
            children: RefCell::new(Vec::new()),
        })
    }

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

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

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

Turn #29Raw score: 1

215 in602 out318 reasoning817 total22.6s

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.

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};

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

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

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

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

    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

215 in1,158 out882 reasoning1,373 total29.3s

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};

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

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

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

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

    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)