leetcode-cpp/0073.cpp at main · s4nj1th/leetcode-cpp · GitHub

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class Solution {
public:
  void setZeroes(vector<vector<int>> &matrix) {
    int n = matrix.size();
    int m = matrix[0].size();
    bool firstRow = false, firstCol = false;

    for (int j = 0; j < m; j++) {
      if (matrix[0][j] == 0)
        firstRow = true;
    }

    for (int i = 0; i < n; i++) {
      if (matrix[i][0] == 0)
        firstCol = true;
    }

    for (int i = 1; i < n; i++) {
      for (int j = 1; j < m; j++) {
        if (matrix[i][j] == 0) {
          matrix[i][0] = 0;
          matrix[0][j] = 0;
        }
      }
    }

    for (int i = 1; i < n; i++) {
      for (int j = 1; j < m; j++) {
        if (matrix[i][0] == 0 || matrix[0][j] == 0) {
          matrix[i][j] = 0;
        }
      }
    }

    if (firstRow) {
      for (int j = 0; j < m; j++)
        matrix[0][j] = 0;
    }

    if (firstCol) {
      for (int i = 0; i < n; i++)
        matrix[i][0] = 0;
    }
  }
};