LeetCode 64. 最小路径和

原题解

题目

约束

题解

class Solution {
public:
    int minPathSum(vector<vector<int>>& grid) {
        if (grid.size() == 0 || grid[0].size() == 0) {
            return 0;
        }
        int m = grid.size();
        int n = grid[0].size();
        vector<vector<int>> dp(m, vector<int>(n));
        dp[0][0] = grid[0][0];
        for(int i = 1; i < m; i ++){
            dp[i][0] = dp[i - 1][0] + grid[i][0];
        }
        for(int j = 1; j < n; j ++){
            dp[0][j] = dp[0][j - 1] + grid[0][j];
        }
        for(int i = 1; i < m; i ++){
            for(int j = 1; j < n; j ++){
                dp[i][j] = min(dp[i - 1][j], dp[i][j - 1]) + grid[i][j];
            }
        }
        return dp[m - 1][n - 1];
    }
};