Minimum Area Rectangle LeetCode solution in C++

1
class Solution {
2
 public:
3
  int minAreaRect(vector<vector<int>> &points) {
4
    unordered_map<int, unordered_set<int>> pts;
5
    for (auto p : points) {
6
      pts[p[0]].insert(p[1]);
7
    }
8

9
    int minArea = INT_MAX;
10
    int n = points.size();
11
    for (int i = 0; i < n; i++) {
12
      for (int j = i + 1; j < n; j++) {
13
        auto p1 = points[i];
14
        auto p2 = points[j];
15
        if (pts[p1[0]].size() < 2 || pts[p2[0]].size() < 2) continue; // added to avoid extra loop
16
        if (p1[0] != p2[0] && p1[1] != p2[1]) {
17
          if (pts[p1[0]].count(p2[1]) > 0 && pts[p2[0]].count(p1[1]) > 0) {
18
            minArea = min(minArea, (abs(p1[0] - p2[0]) * abs(p1[1] - p2[1])));
19
          }
20
        }
21
      }
22
    }
23
    return minArea == INT_MAX ? 0 : minArea;
24
  }
25
};