力扣64. 最小路径和

 

 

题目：【https://leetcode.cn/problems/minimum-path-sum/description/?envType=study-plan-v2&envId=top-interview-150】

 

直接看出来是二维dp，压缩至一维存储，然后就通过了

 

#define NUM_INV 50000
class Solution {
public:
    int minPathSum(vector<vector<int>>& grid) {
        int h = grid.size(), l = grid[0].size();
        vector<int> dp(l, NUM_INV);
        for (int i = 0; i < h; ++i) {
            for (int j = 0; j < l; ++j) {
                if (0 != i || 0 != j) {
                    int a = j - 1 >= 0 ? dp[j - 1] : NUM_INV;
                    dp[j] = grid[i][j] + min(a, dp[j]);
                } else {
                    dp[j] = grid[i][j];
                }
            }
        }
        return dp.back();
    }
};