Leetcode Triangle

Leetcode Triangle 相关代码，使用dp方法完成，c++代码如下，并提供简单的测试代码。

#include <iostream>#include <unordered_set>#include <vector>#include <string>using namespace std;class Solution {public:    int minimumTotal(vector<vector<int> >& triangle) {        if (triangle.size() == 0) {            return 0;        }        int len = triangle.size();        int min;        int pre = 0; // remember the previous re        vector<int> re(len, 0);        re[0] = triangle[0][0];        for (int i = 1; i < len; i ++) {            for (int j = 0; j <= i; j ++) {                // the re[i] has no valid value in the previous line                if (j != i) {                    min = re[j] + triangle[i][j];                }                // the re[-1] is invalid, the pre remember the re[j - 1]                if ((j >= 1 && pre + triangle[i][j] < min) || j == i) {                    min = pre + triangle[i][j];                }                pre = re[j];                re[j] = min;            }        }        min = re[0];        // find the minimal result in re        for (vector<int>::iterator it = re.begin(); it != re.end(); it ++) {            if (*it < min) {                min = *it;            }        }        return min;    }};int main() {    Solution * so = new Solution();    vector<vector<int> > test;    vector<int> a;    a.push_back(-1);    test.push_back(a);    a.clear();    a.push_back(2);    a.push_back(3);    test.push_back(a);    a.clear();    a.push_back(1);    a.push_back(-1);    a.push_back(-3);    test.push_back(a);    cout<<"the minimal result is: "<<so->minimumTotal(test)<<endl;}