求2进制中不同位的个数

#include<stdio.h>
int differe(int num1, int num2) {
  int num = num1 ^ num2;
  int count = 0;
  while (num) {
    num = num & num - 1;
    count++;
  }
}
int main() {
  int a = 0;
  int b = 0;
  scanf_s("%d%d", &a, &b);
  int count = differe(a, b);
  printf("%d", count);
  return 0;
}