1380 - Lucky Numbers in a Matrix

 JAVA

• class Solution {
      public List<Integer> luckyNumbers(int[][] matrix) {
          int m = matrix.length, n = matrix[0].length;
          int[] rows = new int[m];
          int[] cols = new int[n];
          Arrays.fill(rows, 1 << 30);
          for (int i = 0; i < m; ++i) {
              for (int j = 0; j < n; ++j) {
                  rows[i] = Math.min(rows[i], matrix[i][j]);
                  cols[j] = Math.max(cols[j], matrix[i][j]);
              }
          }
          List<Integer> ans = new ArrayList<>();
          for (int i = 0; i < m; ++i) {
              for (int j = 0; j < n; ++j) {
                  if (rows[i] == cols[j]) {
                      ans.add(rows[i]);
                  }
              }
          }
          return ans;
      }
  }

C++

• class Solution {
  public:
      vector<int> luckyNumbers(vector<vector<int>>& matrix) {
          int m = matrix.size(), n = matrix[0].size();
          int rows[m];
          int cols[n];
          memset(rows, 0x3f, sizeof(rows));
          memset(cols, 0, sizeof(cols));
          for (int i = 0; i < m; ++i) {
              for (int j = 0; j < n; ++j) {
                  rows[i] = min(rows[i], matrix[i][j]);
                  cols[j] = max(cols[j], matrix[i][j]);
              }
          }
          vector<int> ans;
          for (int i = 0; i < m; ++i) {
              for (int j = 0; j < n; ++j) {
                  if (rows[i] == cols[j]) {
                      ans.push_back(rows[i]);
                  }
              }
          }
          return ans;
      }
  };