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use std::ops::*;
pub fn extgcd<T>(
a: T,
b: T,
) -> (T, T, T)
where
T: Copy
+ Sub<Output = T>
+ Div<Output = T>
+ Mul<Output = T>
+ Rem<Output = T>
+ From<i32>
+ Ord,
{
if b == 0.into() {
return (a, 1.into(), 0.into());
}
let (g, s, t) = extgcd(b, a % b);
(g, t, s - a / b * t)
}
#[cfg(test)]
mod tests {
use super::*;
#[test]
fn test_extgcd() {
assert_eq!(extgcd(-30, 111), (3, 11, 3));
assert_eq!(extgcd(0, 0), (0, 1, 0));
}
}