Fix typo in modmul-proof.md

Fixes kth-competitive-programming#186.
learn22coding · Jan 4, 2021 · bbb1a53 · bbb1a53
1 parent f3e0ed5
commit bbb1a53
Showing 1 changed file with 1 addition and 1 deletion.
diff --git a/doc/modmul-proof.md b/doc/modmul-proof.md
@@ -6,7 +6,7 @@ typedef int64_t i64;
 typedef long double ld;
 
 u64 modmul(u64 a, u64 b, u64 c) {
-    i64 ret = a * b - M * u64(ld(a) * ld(b) / ld(c));
+    i64 ret = a * b - c * u64(ld(a) * ld(b) / ld(c));
     return ret + c * (ret < 0) - c * (ret >= (i64)c);
 }
 ```