Leetcode #64: Minimum Path Sum

Leetcode_0064.cpp

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