leetcode

Solution to some Leetcode problems written in C++
git clone git://git.dimitrijedobrota.com/leetcode.git
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0840.cpp (969B)

      1 class Solution {
      2   public:
      3     int numMagicSquaresInside(const vector<vector<int>> &grid) const {
      4         const int n = size(grid), m = size(grid[0]);
      5         int res = 0;
      6 
      7         for (int i = 1; i < n - 1; i++) {
      8             for (int j = 1; j < m - 1; j++) {
      9                 if (grid[i][j] != 5) continue;
     10 
     11                 if (grid[i - 1][j - 1] + grid[i - 1][j] + grid[i - 1][j + 1] != 15) continue;
     12                 if (grid[i - 1][j - 1] + grid[i][j - 1] + grid[i + 1][j - 1] != 15) continue;
     13 
     14                 unordered_set<int> us;
     15                 for (int k = i - 1; k <= i + 1; k++) {
     16                     for (int l = j - 1; l <= j + 1; l++) {
     17                         if (grid[k][l] < 1 || grid[k][l] > 9) goto next;
     18                         if (us.count(grid[k][l])) goto next;
     19                         us.insert(grid[k][l]);
     20                     }
     21                 }
     22 
     23                 res++;
     24             next:;
     25             }
     26         }
     27 
     28         return res;
     29     }
     30 };