73. Set Matrix Zeroes 

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class Solution {
    public void setZeroes(int[][] matrix) {
        int m = matrix.length, n = matrix[0].length;

        boolean clearFirstRow = false, clearFirstCol = false;
        for (int j = 0; j < n; j++) {
            if (matrix[0][j] == 0) {
                clearFirstRow = true;
                break;
            }
        }
        for (int i = 0; i < m; i++) {
            if (matrix[i][0] == 0) {
                clearFirstCol = true;
                break;
            }
        }

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

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

References

73. Set Matrix Zeroes
面试题 01.08. 零矩阵