Is Prime

Checking Prime Numbers

Prime numbers are natural numbers greater than 1 that have no positive divisors other than 1 and themselves. Determining whether a number is prime is a fundamental problem in number theory and has applications in various fields, including cryptography and computer science.

In this challenge, you will implement a function to check if a given number is prime. You will use logical operators and conditional statements to handle the multiple conditions required to identify a prime number efficiently.

Your task

Your task is to complete the function is_prime(n: u32) -> bool that takes an unsigned integer n and returns a boolean value indicating whether n is a prime number.

Requirements

The function should return true if n is a prime number and false otherwise.
A prime number is a natural number greater than 1 that is not divisible by any number other than 1 and itself.
Use logical operators and conditional statements to check the conditions for a prime number.
Optimize the function to minimize unnecessary checks.

Example

let result = is_prime(5);
assert_eq!(result, true);
 
let result = is_prime(4);
assert_eq!(result, false);

Hints

Any number less than 2 is not prime.
The number 2 is the only even prime number.
For any other even number greater than 2, return false.
Check divisibility starting from 3 up to the square root of the number.

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Solutions

Carlos Arias

carlos-quantexai

2 hours ago

2.35ms

81.43kb

pub fn is_prime(n: u32) -> bool {
    if n < 2 {
        return false; // Numbers less than 2 are not prime
    }
    for i in 2..=((n as f64).sqrt() as u32) { // Check divisibility up to the square root of n
        if n % i == 0 {
            return false; // Found a divisor, so n is not prime
        }
    }
    true // n is prime
}

Maki-SIO

3 hours ago

2.23ms

81.43kb

pub fn is_prime(n: u32) -> bool {
    if n <= 1 { return false; }
    if n <= 3 { return true; }
    if n % 2 == 0 || n % 3 == 0 { return false; }
    let mut i = 5;
    while i * i < n {
        if n % i == 0 || n % (i + 2) == 0 { return false; }
        i += 6;
    }
    return true;
}

José Bernardo

jose-bernardo

3 hours ago

2.39ms

81.43kb

pub fn is_prime(n: u32) -> bool {
    // Implement your code here
    if n <= 1 { return false; }
    if n <= 3 { return true; }
    if n % 2 == 0 || n % 3 == 0 { return false; }
    let mut i = 5;
    while i * i < n {
        if n % i == 0 || n % (i + 2) == 0 { return false; }
        i += 6;
    }
    return true;
}

Maxence Potier

Mxn-ptr

4 hours ago

2.31ms

81.43kb

pub fn is_prime(n: u32) -> bool {
    // Implement your code here
    if n < 2 {
        return false;
    }
    if n == 2 {
        return true;
    }
    for i in 2..n {
        if n % i == 0 {
            return false;
        } 
    }
    true
}

zelsazgh

5 hours ago

2.38ms

81.43kb

pub fn is_prime(n: u32) -> bool {
    // Implement your code here
    match n {
        1 => false,
        2 => true,
        x if x %2 == 0 => false,
        _ => {
            for i in 3..((n as f32).sqrt() as u32)+1{
                if n % i == 0 {
                    return false
                }
            }
            true
        }
    }
}

Daniel Yan

yansq

7 hours ago

2.28ms

81.43kb

pub fn is_prime(n: u32) -> bool {
    // Implement your code here
    if n < 2 {
        return false;
    }
    if n == 2 {
        return true;
    }
    for i in 2..n {
        if n % i == 0 {
            return false;
        } 
    }
    true
}

brokenstring314

11 hours ago

2.38ms

81.43kb

pub fn is_prime(n: u32) -> bool {
    if n<2 {return false;}
    if n==2 {return true;}
    for i in 2..n {
        if n%i == 0 {return false;}
    }
    true
}

funny_233

funny233-github

11 hours ago

2.33ms

81.43kb

pub fn is_prime(n: u32) -> bool {
    // Implement your code here
    if n < 2 {
        return false;
    }
    for i in 2..n {
        if n % i == 0 {
            return false;
        }
    }
    true
}

Gear

macgeargear

11 hours ago

2.22ms

81.43kb

pub fn is_prime(n: u32) -> bool {
    // Implement your code here
    if n == 1 {
        return false;
    }
    if n == 2 {
        return true;
    }
    if n % 2 == 0 {
        return false;
    }
    println!("{}", (n as f64).sqrt() as u32);
    for i in 3..=(n as f64).sqrt() as u32 {
        if n % i == 0 {
            return false;
        }
    }
    true
}

Delta Regeer

digitalresistor

19 hours ago

2.50ms

81.43kb

pub fn is_prime(n: u32) -> bool {
    if n == 2 {
        return true;
    }
    if n < 2 || n & 0x1 == 0 {
        return false;
    }
    let num_sqrt: u32 = f32::sqrt(n as f32) as u32 + 1;
    for tester in 3..=num_sqrt {
        if n % tester == 0 {
            return false;
        }
    }
    return true;
}

Logan Radloff

radloffl

a day ago

2.30ms

81.43kb

pub fn is_prime(n: u32) -> bool {
    // Implement your code here
    match n {
        x if x < 2 => false,
        2 => true,
        x if x % 2 == 0 => false,
        _ => {
            let sq = ((n as f32).sqrt() as u32) + 1;
            for x in 3..=sq {
                if n % x == 0 {
                    return false;
                }
            }
            return true;
        }
    }
}

majesticalcreature

a day ago

2.34ms

87.09kb

pub fn is_prime(n: u32) -> bool {
    // Implement your code here
    let lim = (n as f32).sqrt() as u32;
    let mut list: Vec<u32> = (2..n+1).collect();
    if n < 2 {
        return false;
    }
    loop {
        let div = *list.first().unwrap();
        if div > lim {
            break;
        }
        list.retain(|x| x%div != 0);
        if list.is_empty() {
            break;
        }
        if *(list.last().unwrap()) != n {
            return false;
        }
    }
    true
}

今何求

jhq223

2 days ago

2.38ms

81.43kb

pub fn is_prime(n: u32) -> bool {
    if n < 2 {
        return false;
    }
    for i in 2..((n as f32).sqrt() as u32) + 1 {
        if n % i == 0 {
            return false;
        }
    }
    return true;
}

Will Barnett

xbarnett

2 days ago

2.30ms

81.43kb

pub fn is_prime(n: u32) -> bool {
    if n <= 1 {
        return false;
    }
    let mut d: u32 = 2;
    while d * d <= n {
        if n % d == 0 {
            return false;
        }
        d += 1;
    }
    true
}

Johnchoi913

2 days ago

2.27ms

81.43kb

pub fn is_prime(n: u32) -> bool {
    // Implement your code here
    if n < 2 {
        return false;
    }
    let sqrt = (n as f64).sqrt() as u32;
    for x in 2..=sqrt {
        if n % x == 0 {
            return false;
        }
    }
    true
}

Matei Stefanescu

matei

2 days ago

2.28ms

81.43kb

pub fn is_prime(n: u32) -> bool {
    if n < 2 {
        return false;
    }
    if n == 2 {
        return true;
    }
    if n % 2 == 0 {
        return false;
    }
    for i in 3..n-1 {
        if n % i == 0 {
            return false;
        }
    }
    true
}

sander-b-postnl

2 days ago

2.39ms

81.43kb

pub fn is_prime(n: u32) -> bool {
    n > 1 && (2..=(n as f64).sqrt() as u32).all(|i| n % i != 0)
}

Ustin

2 days ago

2.39ms

81.43kb

pub fn is_prime(n: u32) -> bool {
    // Implement your code here
    if n < 2  {return false;};
    if n == 2 {return true;};
    for i in 2..n {
        if n % i == 0 {return false};
    }
    true
}

Ojash Neopane

oneopane

2 days ago

2.17ms

81.43kb

pub fn is_prime(n: u32) -> bool {
    if n == 1 {
        return false;
    }
    for counter in 2..((n as f64).sqrt() as u32 + 1) {
        if n % counter == 0 {
            return false;
        }
    }
    true
}

amassare

2 days ago

2.35ms

81.43kb

pub fn is_prime(n: u32) -> bool {
    // Implement your code here
    n>1&&!(2..n).any(|x|n%x==0)
}

amassare

2 days ago

2.28ms

81.43kb

pub fn is_prime(n: u32) -> bool {
    // Implement your code here
    if n==1{
        return false;
    }
    !(2..n).any(|x|n%x==0)
}

Oleksandr Romanov

alexromanov

2 days ago

2.19ms

81.43kb

pub fn is_prime(n: u32) -> bool {
    // Implement your code here
    if n < 2 {
        return false;
    }
    for i in 2..(f64::from(n).sqrt() as u32) + 1 {
        if n % i == 0 {
            return false;
        }
    }
    return true;
}

Stefano Cianciulli

CianciuStyles

2 days ago

2.43ms

81.43kb

pub fn is_prime(n: u32) -> bool {
    // Implement your code here
    if n < 2 { return false }
    for i in 2..(f64::from(n).sqrt() as u32)+1 {
        if n % i == 0 {
            return false
        }
    }
    true
}

Joel Vicente Filho

kyhou

3 days ago

2.42ms

81.43kb

pub fn is_prime(n: u32) -> bool {
    // Implement your code here
    if n < 2
    {
        return false;
    }
    if n == 2 {
        return true;
    }
    if n % 2 == 0 {
        return false;
    }
    for x in 3..=(n as f64).sqrt() as u32 
    {
        if n % x == 0 {
            return false;
        }
    }
    true
}

Adi

Aditeya

3 days ago

2.31ms

81.43kb

pub fn is_prime(n: u32) -> bool {
    // Implement your code here
    if n < 2 { return false; }
    if n == 2 { return true; }
    if n % 2 == 0 { return false; }
    let n_sqrt = (n as f64).sqrt().ceil() as u32;
    for i in (3..=n_sqrt).step_by(2) {
        if n % i == 0 {
            return false;
        }
    }
    true
}

Ayush Rawat

ayushrawat10

3 days ago

2.33ms

81.43kb

pub fn is_prime(n: u32) -> bool {
    if n < 2 {
        return false;
    }
    if n == 2 {
        return true; 
    }
    if n % 2 == 0 {
        return false;
    }
    for i in 3..=((n as f32).sqrt() as u32) {
        if i*i == n {
            return false;
        }
    }
    return true;
}

Patrik Bjärterot

pbjarterot

3 days ago

2.49ms

81.43kb

pub fn is_prime(n: u32) -> bool {
  if n < 2 {
        false
    }
    else if n == 2 {
        true
    }
    else if n > 2 && n % 2 == 0 {
        false
    }
    else {
        for i in 3..=((n as f64).sqrt() as u32) {
            if n % i == 0 {
                return false;
            }
        }
        true
    }
}

masteryachty

3 days ago

2.36ms

81.43kb

pub fn is_prime(n: u32) -> bool {
    // Implement your code here
    if n < 2 {
        false
    }
    else if n == 2 {
        true
    }
    else if n > 2 && n % 2 == 0 {
        false
    }
    else {
        for i in 3..=((n as f64).sqrt() as u32) {
            if n % i == 0 {
                return false;
            }
        }
        true
    }
}

damascussteel21

3 days ago

2.25ms

81.43kb

pub fn is_prime(n: u32) -> bool {
    // Implement your code here
    if n < 2 {
        false
    }
    else if n == 2 {
        true
    }
    else if n > 2 && n % 2 == 0 {
        false
    }
    else {
        for i in 3..=((n as f64).sqrt() as u32) {
            if n % i == 0 {
                return false;
            }
        }
        true
    }
}

John Truong

jtruong04

4 days ago

2.41ms

81.43kb

pub fn is_prime(n: u32) -> bool {
    // Implement your code here
    if n <=1 {
        return false;
    }
    for i in 2..(f64::from(n).sqrt() as u32)+1 {
        if n % i == 0 {
            return false;
        }
    }
    true
}

Abhiyan Chhetri

abhiyan-chhetri

4 days ago

2.31ms

81.43kb

pub fn is_prime(n: u32) -> bool {
    if n < 2 { return false; }
    
    let sq = (n as f32).sqrt() as u32;
    
    for x in 2..=sq {
        if n % x == 0 {
            return false;
        } 
    }
    return true;
}

Edgar Christian

edgarcnp

4 days ago

2.27ms

81.43kb

pub fn is_prime(n: u32) -> bool {
    if n < 2 { return false; }
    for i in 2..=(n as f32).sqrt() as u32 {
        if n % i == 0 { return false; }
    }
    true
}

Samuel

Sommos

4 days ago

2.33ms

81.43kb

pub fn is_prime(n: u32) -> bool {
    // Implement your code here
    if n <= 1 {
        return false
    }
    for i in 2..n {
        if n % i == 0 {
            return false
        }
    }
    return true
}

Christian Franzl

wischi-chr

4 days ago

2.26ms

81.43kb

pub fn is_prime(n: u32) -> bool {
    if n < 2 {
        return false;
    }
    let limit = (n as f64).sqrt().floor() as u32;
    for d in 2..=limit {
        if n % d == 0 {
            return false
        }
    }
    true
}

Tukan van der Borgh

tukantje

4 days ago

2.43ms

85.89kb

pub fn is_prime(n: u32) -> bool {
    let upper_limit = (n as f32).sqrt() as u32 + 1;
    if n < 2 {
        return false;
    }
    for i in 2..upper_limit {
        if n % i == 0 {
            return false;
        }
    }
    true
}

Danny Yoo

dyoo

5 days ago

2.54ms

81.43kb

pub fn is_prime(n: u32) -> bool {
    match n {
        0 | 1 => false,
        _ => (2..n).filter(|div| n % div == 0).count() == 0
    }
}

Jason Green

jaswgreen

5 days ago

2.18ms

81.43kb

pub fn is_prime(n: u32) -> bool {
    // Implement your code here
    if n == 1 {
        return false
    }
    for divisor in 2..=(n as f64).sqrt() as u32 {
        if n % divisor == 0 {
            return false
        }
    }
    true
}

Nicolás Caracci

hilias

5 days ago

2.23ms

81.43kb

pub fn is_prime(n: u32) -> bool {
    // Implement your code here
    if n < 2 {
        return false;
    } else if n == 2 {
        return true;
    } else if n % 2 == 0 {
        return false;
    }
    let max_n = (n as f64).sqrt() as u32 + 1;
    for test in (3..max_n).step_by(2) {
        if n % test == 0 {
            return false;
        }
    }
    true
}

CarrotTarrot

5 days ago

2.26ms

81.43kb

pub fn is_prime(n: u32) -> bool {
    if n == 1 {
        return false
    }
    for divisor in 2..=(n as f64).sqrt() as u32 {
        if n % divisor == 0 {
            return false
        }
    }
    true
}

CarrotTarrot

5 days ago

2.36ms

81.43kb

pub fn is_prime(n: u32) -> bool {
    if n == 1 {
        return false
    }
    for divisor in 2..=n/2 {
        if n % divisor == 0 {
            return false
        }
    }
    true
}

Hin Phansa

hinphansa

5 days ago

2.14ms

81.43kb

pub fn is_prime(n: u32) -> bool {
    // Implement your code here
    if n < 2 {
        return false;
    }
    let n_max: u32 = (n as f64).sqrt() as u32 + 1;
    for i in 2..n_max {
        if n % i == 0 {
            return false;
        }
    }
    return true;
}

Hin Phansa

hinphansa

5 days ago

2.60ms

85.89kb

pub fn is_prime(n: u32) -> bool {
    // Implement your code here
    if n < 2 {
        return false;
    }
    let n_max: u32 = (n as f64).sqrt() as u32;
    for i in 2..(n_max + 1) {
        if n % i == 0 {
            return false;
        }
    }
    return true;
}

Quentin Cabanes

qcabanes-hobby

5 days ago

2.30ms

81.43kb

pub fn is_prime(n: u32) -> bool {
    if n < 2 {
        return false;
    } else if n == 2 {
        return true;
    } else if n % 2 == 0 {
        return false;
    } else {
        for x in 3..=((n as f64).sqrt() as u32) {
            if n % x == 0 {
                return false;
            }
        }
    }
    return true;
}

TaiPoole

5 days ago

2.36ms

81.43kb

pub fn is_prime(n: u32) -> bool {
    match n {
        0 | 1 => false,
        _ => !(2..((n as f64).sqrt() as u32 + 1)).any(|x| n % x == 0)
    }
}

TomBaston

5 days ago

2.25ms

81.43kb

pub fn is_prime(n: u32) -> bool {
    // Implement your code here
    match n {
        0 | 1 => false,
        2 => true,
        _ if n & 1 == 0 => false,
        _ => {
            let sqrt_n = (n as f64).sqrt() as u32;
            for f in (3..=sqrt_n).filter(|x| x & 1 != 0) {
                if n % f == 0 {
                    return false;
                }
            }
            true
        }
    }
}

Stephan Roslen

stephanroslen

5 days ago

2.15ms

81.43kb

pub fn is_prime(n: u32) -> bool {
    if n < 2 {
        return false;
    }
    for candidate in 2..n {
        if candidate * candidate > n {
            break;
        }
        if n % candidate == 0 {
            return false;
        }
    }
    return true;
}

swandyr

5 days ago

2.17ms

87.16kb

pub fn is_prime(n: u32) -> bool {
    // Implement your code here
    match n {
        0 | 1 => false,
        2 => true,
        n if n % 2 == 0 => false,
        n => {
            dbg!(n);
            for i in 3..=((n as f64).sqrt().floor() as u32) {
                if n % i == 0 {
                    return false;
                }
            }
            true
        }
    }
}

Nithin S Varrier

0x006E

5 days ago

2.36ms

81.43kb

pub fn is_prime(n: u32) -> bool {
    // Implement your code here
    if n < 2 {
        return false
    }
    for i in 2..n {
        if n % i == 0 {
            return false;
        }
    }
    true
}

Frisc98

5 days ago

2.23ms

81.43kb

pub fn is_prime(n: u32) -> bool {
    // Implement your code here
    if n == 1{
        return false;
    }
    let mut i:u32 = 2;
    while i<n/2 + 1{
        if n % i == 0{
            return false;
        }
        i+= 1;
    }
    return true;
}

alspadoni

5 days ago

2.48ms

81.43kb

pub fn is_prime(n: u32) -> bool {
    // Implement your code here
    if n < 2 {
        return false;
    }
    if n < 4 {
        return true;
    }
    for i in 2..n {
        if n % i == 0 {
            return false;
        }
    }
    return true;
}