Write an algorithm such that if an element in an MxN matrix is 0, its entire row and columns are set to 0

Question

For this question, I implemented this:

public void setZeros (int[][] matrix) {
    firstScan(matrix);
    secondScan(matrix);
}

public void firstScan(int[][] matrix) {
    int i,  j;
    for (i =0; i < matrix.length; i++) {
        for (j = 0; j < matrix[0].length; j++)
        {if (matrix[i][j] == 0) {markRowsAndColums(matrix ,i,j);
        }}}}

public void secondScan(int[][] matrix) {
    int i,  j;
    for (i =0; i < matrix.length; i++) {
        for (j = 0; j < matrix[0].length; j++) { if (matrix[i][j] == -1)  {
            matrix[i][j]= 0;
        }}}}

public void markRowsAndColums (int[][] matrix, int i,int j) {
    for ( int x = 0; x< matrix[0].length; x++ ) {
        if(matrix[i][x] !=0) {matrix[i][x] = -1;}}
    for ( int x = 0; x< matrix.length; x++ ) {
        if(matrix[x][j] !=0) {matrix[x][j] = -1;}
    }}

My first scan aims to change all rows and columns that have zeros into -1s (but not the zeros).

My second scan aims to convert all the -1s into zeros.

Do you think it is a good solution? Does it work? And I don't know what the runtime of the algorithm is. It would be great if you could give me a hint cuz I really have no idea.