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Chinese Remainder: Avoid map/zip/map courtesy of mamad :3

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This commit is contained in:
Guilhem MARION
2021-02-08 18:55:40 +11:00
parent 15d9bb216a
commit fc8d16b6b8
1 changed files with 2 additions and 4 deletions
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6
chinese_remainder/src/lib.rs
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@@ -46,11 +46,9 @@ pub fn chinese_remainder(residues: &[i64], moduli: &[i64]) -> Option<i64> {
// TODO: Filter out 0s in moduli (meaning big_n is 0 -> div by 0) // TODO: Filter out 0s in moduli (meaning big_n is 0 -> div by 0)
let big_n: i64 = moduli.iter().product(); let big_n: i64 = moduli.iter().product();
Some(moduli.iter() Some(moduli.iter()
.map(|&ni| {
egcd(ni, big_n / ni)
})
.zip(residues) .zip(residues)
.map(|(egcd,ai)| { .map(|(&ni, ai)| {
let egcd = egcd(ni, big_n / ni);
if egcd.gcd != 1 { if egcd.gcd != 1 {
// Fail in case moduli are not co-prime // Fail in case moduli are not co-prime
None None