Calculate Amount Paid in Taxes LeetCode solution in C++

1
class Solution {
2
 public:
3
  double calculateTax(vector<vector<int>> &brackets, int income) {
4
    double ans = 0;
5
    int back = 0;
6
    for (auto x : brackets) {
7
      int upper = x[0], percent = x[1];
8
      if (upper > income) {
9
        ans += (income - back) * percent;
10
        break;
11
      } else
12
        ans += (upper - back) * percent;
13
      back = upper;
14
    }
15
    return (ans / 100);
16
  }
17
};