Leetcode120.Triangle

Posted 2020-08-14 Liez

[Question]

 

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).

 

[Solution]

//C++

class Solution {
public:
    int minimumTotal(vector& triangle) {
        if(triangle.size()==0)
            return 0;

        if(triangle.size()==1)
            return(triangle[0][0]);

        for(int i=triangle.size()-2; i>=0; i--){
            for(int j=0; j<=i; j++){
                triangle[i][j] += min(triangle[i+1][j], triangle[i+1][j+1]);
            }
        }
        return triangle[0][0];
    }
};