LeetCode: Triangle

基本一次过

 1 class Solution {

 2 public:

 3     int minimumTotal(vector<vector<int> > &triangle) {

 4         // Start typing your C/C++ solution below

 5         // DO NOT write int main() function

 6         if (!triangle.size()) return 0;

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

 8         vector<int> pre = triangle[0];

 9         for (int i = 1; i < triangle.size(); i++) {

10             vector<int> tmp = pre;

11             for (int j = 0; j < pre.size(); j++) {

12                 if (!j) tmp[j] = pre[j] + triangle[i][j];

13                 else tmp[j] = min(pre[j-1], pre[j]) + triangle[i][j];

14             }

15             tmp.push_back(triangle[i][i]+pre[pre.size()-1]);

16             pre = tmp;

17         }

18         int ret = pre[0];

19         for (int i = 1; i < pre.size(); i++) ret = min(ret, pre[i]);

20         return ret;

21     }

22 };