Add One

#include <iostream>
#include <climits>
using namespace std;

/*
  Given an integer, add its binary number by 1 without using '+'.
*/

int addOne(int number) {
  long long int a = number;
  if(a >= INT_MAX) return -1;  // may need to talk to interviewer.
  int sum = number ^ 1;
  int carry = (number & 1) << 1;
  while(carry != 0) {
    int tmp = sum;
    sum = sum ^ carry;
    carry = (sum & 1) << 1;
  }
  return sum;
}

int main(void) {
  cout << addOne(INT_MAX) << endl;
}

#include <iostream>
#include <vector>
using namespace std;

/*
  Moving non-zero elements, order doesn't matter.
*/
void moveNonzero(vector<int>& nums) {
  if(nums.size() == 0) return;
  int i = 0;
  int j = nums.size() - 1;
  while(i < j) {
    if(nums[i] == 0) {
      swap(nums[i], nums[j]);
      j--;
    } else i++;
  }
  return;
}

int main(void) {
  vector<int> nums{0, 1, 0, 2};
  moveNonzero(nums);
  for(int i = 0; i < nums.size(); ++i) {
    cout << nums[i] << " ";
  }
  cout << endl;
}