Leetcode 120. Triangle (Medium) (cpp)

Leetcode 120. Triangle (Medium) (cpp)

Tag: Array, Dynamic Programming

Difficulty: Medium

/*120. Triangle (Medium)Given a triangle, find the minimum path sum from top to bottom. Each step you may move to adjacent numbers on the row below.For example, given the following triangle[     [2],    [3,4],   [6,5,7],  [4,1,8,3]]The minimum path sum from top to bottom is 11 (i.e., 2 + 3 + 5 + 1 = 11).Note:Bonus point if you are able to do this using only O(n) extra space, where n is the total number of rows in the triangle.*/class Solution {public:int minimumTotal(vector<vector<int>>& triangle) {vector<int> res = triangle.back();for (int i = triangle.size() - 2; i >= 0; i--) {for (int j = 0; j < triangle[i].size(); j++) {res[j] = min(res[j], res[j + 1]) + triangle[i][j];            }}return res[0];}};