/// Finds the greatest common divisor
////// # Examples
////// ```
/// let a = 10;
/// let b = 15;
////// assert_eq!(math_utils::gcd(a, b), 5);
/// ```
///pubfngcd(muta:u64, mutb:u64)->u64{assert!(a !=0&& b !=0);while b !=0{if b < a {let t = b;
b = a;
a = t;}
b = b % a;}
a
}#[cfg(test)]modtests{use::*;#[test]fntest_gdc(){assert_eq!(gcd(14,15),1);assert_eq!(gcd(2*3*5*11*17,3*7*11*13*19),3*11);}}