https://leetcode.cn/problems/minimum-path-sum/submissions/
class Solution {
public:
    int minPathSum(vector<vector<int>>& grid) {
        if(grid.empty()) return 0;
        int m = grid.size();
        int n = grid[0].size();
        vector<vector<int>> dp(m+1, vector<int>(n+1, INT_MAX));
        // 初始化为INT_MAX整形最大值, dp[0][1]位置初始化为1
        dp[0][1]=0;
        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-1][j-1];
            }
        }

        return dp[m][n];
    }
};