Leetcode73. Matrix Zeroing

题目传送地址： https://leetcode.cn/problems/set-matrix-zeroes/

运行效率

代码如下：

class Solution {
    
  public static void setZeroes(int[][] matrix) {
    
  //First find a number that does not exist in the matrix, At that time, set the horizontal and vertical positions to this number,Finally, put in the matrix0After it's all done,Change the number to 0
        BitSet bitSet = new BitSet();
        for (int i = 0; i < matrix.length; i++) {
    
            for (int j = 0; j < matrix[0].length; j++) {
    
                if (matrix[i][j] <= 400 && matrix[i][j] >= 0) {
    
                    bitSet.set(matrix[i][j]);
                }
            }
        }
        int val = bitSet.nextClearBit(0);


        for (int row = 0; row < matrix.length; row++) {
    
            for (int col = 0; col < matrix[0].length; col++) {
    
                if (matrix[row][col] == 0) {
    
                    fillVal(row, col, matrix, val);
                }
            }
        }
        for (int i = 0; i < matrix.length; i++) {
    
            for (int j = 0; j < matrix[0].length; j++) {
    
                if (matrix[i][j] == val) {
    
                    matrix[i][j] = 0;
                }
            }
        }
    }


    public static void fillVal(int row, int col, int[][] matrix, int val) {
    
        //Set everything on the horizontal line of the coordinate to 0, 除非遇到matrix里自带的0才截止
        for (int i =0; i < matrix[0].length; i++) {
    
            if (matrix[row][i] != 0) {
    
            
                matrix[row][i] = val;
            }
        }
        //Set everything on the vertical line of the coordinate to 0, 除非遇到matrix里自带的0才截止
        for (int j =0; j < matrix.length; j++) {
    
            if (matrix[j][col] != 0) {
    
                matrix[j][col] = val;
            }
        }
    }


}