73-set-matrix-zeroes

DevGod

Elf Vtuber

Caution

DevGod needs to write an editorial for this problem!

js

/**
 * @param {number[][]} matrix
 * @return {void} Do not return anything, modify matrix in-place instead.
 */
var setZeroes = function(matrix) {
    let firstRow = false;
    let firstCol = false;
    for(let row = 0; row<matrix.length; row++){
        for(let col = 0; col<matrix[0].length; col++){
            if(matrix[row][col] === 0){
                if(row === 0){firstCol = true;}
                if(col === 0){firstRow = true;}
                matrix[row][0] = 0;
                matrix[0][col] = 0;
            }
        }
    }

    for(let row = 1; row<matrix.length; row++){
        for(let col = 1; col<matrix[0].length; col++){
            if( matrix[row][0] === 0 || matrix[0][col] === 0){
                matrix[row][col] = 0;
            }
        }
    }

    if(firstRow){
        for(let row = 0; row<matrix.length; row++){
            matrix[row][0] = 0;
        }
    }

    if(firstCol){
        for(let col = 0; col<matrix[0].length; col++){
            matrix[0][col] = 0;
        }
    }
};