The Solution to LeetCode 120 Triangle

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).

Answer:

//本题我的解法是利用树的递归。

class Solution {
public:
    int minimumTotal(vector<vector<int>>& triangle) {
        return min(triangle, 0, 0);  
    }  
      
    int min(vector<vector<int>> &triangle, int level, int i)  
    {  
        if(level == triangle.size()-1)  
        {  
            return triangle[level][i];  
        }  
        else  
        {  
            int left = min(triangle, level + 1, i);  
            int right = min(triangle, level + 1, i+1);  
              
            return left<right?(left+triangle[level][i]):(right+triangle[level][i]);  
        }  
    }  
}; 

Run Code Result:

Your input

[[2],  [3,4], [6,5,7]]

Your answer

10

Expected answer

10