i升序：

class Solution {
public:
    int dp[1010];
    int minimumTotal(vector<vector<int>>& triangle) {
        int i,j;
        dp[0]=triangle[0][0];
        int val;
        for(i=1;i<triangle.size();i++)
            for(j=0;j<triangle[i].size();j++)
            {
                if(j-1<0)
                {
                    val=dp[j];
                    dp[j]=triangle[i][j]+dp[j];
                }
                else
                {
                    if(j>=triangle[i-1].size()) 
                    {
                        dp[j]=triangle[i][j]+val;
                        val=dp[j];
                    }
                    else
                    {
                        int tmp=triangle[i][j]+min(val,dp[j]);
                        val=dp[j];
                        dp[j]=tmp;
                    }
                }
            }
        int ans=INT_MAX;
        for(j=0;j<triangle[i-1].size();j++)
            ans=min(ans,dp[j]);
        return ans;
    }
};

i降序：

class Solution {
public:
    int dp[1010];
    int minimumTotal(vector<vector<int>>& triangle) {
        int i,j;
        if(triangle.size()==1)
            return triangle[0][0];
        for(j=0;j<triangle[triangle.size()-1].size();j++)dp[j]=triangle[triangle.size()-1][j];
        int val;
        for(i=triangle.size()-2;i>0;i--)
        {
            for(j=0;j<triangle[i].size();j++)
            {
                dp[j]=triangle[i][j]+min(dp[j],dp[j+1]);
            }

        }
        return triangle[0][0]+min(dp[0],dp[1]);
    }
};