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1318 - Minimum Flips to Make a OR b Equal to c (Medium)

https://leetcode.com/problems/minimum-flips-to-make-a-or-b-equal-to-c/

Problem Statement​

Given 3 positives numbers a, b and c. Return the minimum flips required in some bits of a and b to make ( a OR b == c ). (bitwise OR operation). Flip operation consists of change any single bit 1 to 0 or change the bit 0 to 1 in their binary representation.

Example 1:

Input: a = 2, b = 6, c = 5
Output: 3
Explanation: After flips a = 1 , b = 4 , c = 5 such that (a OR b == c)

Example 2:

Input: a = 4, b = 2, c = 7
Output: 1

Example 3:

Input: a = 1, b = 2, c = 3
Output: 0

Constraints:

  • 1≤a≤1091 \le a \le 10^9
  • 1≤b≤1091 \le b \le 10^9
  • 1≤c≤1091 \le c \le 10^9

Approach 1: Bit Manipulation​

Written by @Recedivies
class Solution {
public:
    int minFlips(int a, int b, int c) {
        int ans = 0;
        for (int i = 0; i <= 30; i++) {
            bool bitA = a & (1<<i) ? 1 : 0;
            bool bitB = b & (1<<i) ? 1 : 0;
            bool bitC = c & (1<<i) ? 1 : 0;
            if (bitC){
                if (!(bitA|bitB)) ans++;
            }
            if (!bitC){
                if (bitA) ans++;
                if (bitB) ans++;
            }
        }
        return ans;
    }
};