Removing stupid multMod.

1 files changed, 4 insertions, 12 deletions

diff --git a/math/modExp.cpp b/math/modExp.cpp
index 967068c..d74eca0 100644
--- a/math/modExp.cpp
+++ b/math/modExp.cpp
@@ -1,15 +1,7 @@
 // Laufzeit: O(log(b))
-ll multMod(ll a, ll b, ll n) {
-	if(a == 0 || b == 0) return 0;
-	if(b == 1) return a % n;
-	if(b % 2 == 1) return (a + multMod(a, b-1, n)) % n;
-	else return multMod((a + a) % n, b / 2, n);
-}
-
-// Laufzeit: O(log(b))
 ll powMod(ll a, ll b, ll n) {
-	if(b == 0) return 1;
-	if(b == 1) return a % n;
-	if(b % 2 == 1) return multMod(powMod(a, b-1, n), a, n);
-	else return powMod(multMod(a, a, n), b / 2, n);
+  if(b == 0) return 1;
+  if(b == 1) return a % n;
+  if(b & 1) return (powMod(a, b - 1, n) * a) % n;
+  else return powMod((a * a) % n, b / 2, n);
 }