问题描述:Given a m x n matrix, if an element is 0, set its entire row and column to 0. Do it in place.
问题分析:由题意可知,基本思路就是维持一个长度为m和一个长度为n的数组,用来标注哪些行和哪些列为零。由头到尾遍历一遍整个矩阵,然后再根据所维持的数组,对原矩阵的对应元素进行置零操作。
实现代码:
class Solution {
public:
void setZeroes(vector>& matrix) {
int m = matrix.size();
int n = matrix[0].size();
vector row,column;
row.resize(m);
row = {0};
column.resize(n);
column = { 0 };
for (int i = 0; i < m; i++)
{
for (int j = 0; j < n; j++)
{
if (matrix[i][j] == 0)
{
row[i] = 1;
column[j] = 1;
}
}
}
for (int k1 = 0; k1 < n; k1++)
{
for (int k2 = 0; k2 < matrix.size(); k2++)
{
if(row[k2]==1||column[k1]==1)
{
matrix[k2][k1] = 0;
}
}
}
}
};