04_SetZerosMatrix.py

# Question link - https://leetcode.com/problems/set-matrix-zeroes/description/?envType=study-plan-v2&envId=top-interview-150

class Solution:
    def setZeroes(self, matrix: List[List[int]]) -> None:
        """
        Do not return anything, modify matrix in-place instead.
        """
        n = len(matrix)
        m = len(matrix[0])
        # let variables 
        col0 = 1 
        for i in range(n):
            for j in range(m):
                if matrix[i][j] == 0:
                    matrix[i][0] = 0
                    if j!= 0:
                        matrix[0][j] = 0
                    else:
                        col0 = 0

        # Marks the 0 from (1,1) to (n-1) (m-1)
        for i in range(1,n):
            for j in range(1,m):
                if matrix[i][j] != 0:
                    if matrix[i][0] == 0 or matrix[0][j] == 0:
                        matrix[i][j] = 0

        if matrix[0][0] == 0:
            for j in range(m):
                matrix[0][j] = 0
            
        if col0 == 0:
            for i in range(n):
                matrix[i][0] = 0

        return matrix