LintCode Flip Bits

Determine the number of bits required to flip if you want to convert integer n to integer m.
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Example
Given n = 31 (11111), m = 14 (01110), return 2.
Note
Both n and m are 32-bit integers.

class Solution {
public:
    /**
     *@param a, b: Two integer
     *return: An integer
     */
    int bitSwapRequired(int a, int b) {
        // write your code here
        int diff = a ^ b;
        int count = 0;
        while (diff) {
            count++;
            diff = diff & (diff - 1);
        }
        return count;
    }
};