Leetcode 细节实现 Set Matrix Zeroes

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Set Matrix Zeroes

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

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题意：给定矩阵，如果矩阵的某个位置为0，则把那一行那一列的所有元素都置为0
思路：用两个bool数组，分别记录应该把所有元素置为0的行和列
复杂度：时间O(m*n)，空间O(m+n)

void setZeroes(vector<vector<int> > &matrix){if(matrix.empty()) return ;int rows = matrix.size(), columns = matrix[0].size();vector<bool> row(rows, false);vector<bool> column(columns, false);for(int i = 0; i < rows; ++i){for(int j = 0; j < columns; ++j){if(matrix[i][j] == 0){row[i] = column[j] = true;continue;}}}for(int i = 0; i < rows; ++i){if(!row[i]) continue;for(int j = 0; j < columns; ++j){matrix[i][j] = 0;}}for(int j = 0; j < columns; ++j){if(!column[j]) continue;for(int i = 0; i < rows; ++i){matrix[i][j] = 0;}}}

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