73-Set-Matrix-Zeroes.py

class Solution:
    def setZeroes(self, matrix: List[List[int]]) -> None:
        \\\
        Do not return anything, modify matrix in-place instead.
        \\\
        rows, cols = len(matrix), len(matrix[0])
        zero_rows, zero_cols = set(), set()

        for r in range(rows): # to find
            for c in range(cols):
                if matrix[r][c] == 0:
                    zero_rows.add(r)
                    zero_cols.add(c)

        for r in range(rows): # to set
            for c in range(cols):
                if r in zero_rows or c in zero_cols:
                    matrix[r][c] = 0