Update mult.py: branchless, compact

daedalus · Feb 10, 2024 · 3f01f59 · 3f01f59
1 parent 11da0b7
commit 3f01f59
Showing 1 changed file with 6 additions and 6 deletions.
diff --git a/mult.py b/mult.py
@@ -1,15 +1,15 @@
 def mult(x, y):
     z = 0
     while y > 0:
-        z = z + x
-        y = y - 1
+        z += x
+        y -= 1
     return z
 
 
 def russian_peasant(x, y):
     z = 0
     while y > 0:
-        if y % 2 == 1: z = z + x
-        x = x << 1
-        y = y >> 1
-    return z 
+        z += x * (y & 1) 
+        x <<= 1
+        y >>= 1
+    return z