Leetcode 64. 最小路径和

动态规划

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

        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];
    }
};