Leetcode - Set Matrix Zeroes

https://leetcode.com/problems/set-matrix-zeroes/

Given a m x n matrix, if an element is 0, set its entire row and column to 0. Do it in-place.

Example 1:

Input: 
[
  [1,1,1],
  [1,0,1],
  [1,1,1]
]
Output: 
[
  [1,0,1],
  [0,0,0],
  [1,0,1]
]

1. If meet a 0, set first column or first row to 0. If the first row or column is 0, use two variables to mark it.

2. Loop from 1, if the first column or the first row is 0, mark the current element to 0

3. If the first row is 0, loop the column and mark 0; if the first column is 0, loop the row and mark 0.

func setZeroes(matrix [][]int)  {
    if len(matrix) == 0 || len(matrix[0]) == 0 {
        return
    }
    row := len(matrix)
    column := len(matrix[0])
    firstRow := false
    firstColumn := false
    
    for i := 0; i < row; i++ {
        for j := 0; j < column; j++ {
            if matrix[i][j] == 0 {
                if i == 0 {
                    firstRow = true
                }
                if j == 0 {
                    firstColumn = true
                }
                matrix[0][j] = 0
                matrix[i][0] = 0
            }
        }
    }
    for i := 1; i < row; i++ {
        for j := 1; j < column; j++ {
            if matrix[i][0] == 0 || matrix[0][j] == 0 {
                matrix[i][j] = 0
            }
        }
    }
    if firstRow {
        for j := 0; j < column; j++ {
            matrix[0][j] = 0
        }
    }
    if firstColumn {
        for i := 0; i < row; i++ {
            matrix[i][0] = 0
        }
    }
}

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