Create 12. Minimum Flips to Make a OR b Equal to c.py

17_Bit-Manipulation/12. Minimum Flips to Make a OR b Equal to c.py

@@ -0,0 +1,17 @@
+# https://leetcode.com/problems/minimum-flips-to-make-a-or-b-equal-to-c/
+
+class Solution:
+    def minFlips(self, a: int, b: int, c: int) -> int:
+        res = 0
+        for i in range(32):
+            if (a & 1) | (b & 1) != (c & 1):
+                if (c & 1) == 1:  # (a & 1) | (b & 1) should be == 1 ; so changing any of a, b we can get 1
+                    res += 1      
+                else:             # (a & 1) | (b & 1) should be == 0 ; is (a & 1) == 1 and (b & 1) == 1 we need to change both to 0 so res += 1; if any of them is 1 then change only 1 i.e. res += 1
+                    res += (a & 1) + (b & 1) 
+            a, b, c = a>>1, b>>1, c>>1   # left-shift by 1
+
+        return res
+
+# Time: O(1)
+# Space: O(1)