Pascal's Triangle
//注意容器的空间,如果没有预设好,[]访问会出错的。。。。
---这个很容易出问题。
vector<vector<int> > generate(int numRows) { // Note: The Solution object is instantiated only once and is reused by each test case. vector<vector<int>> res; if(numRows<=0) return res; res.resize(numRows,vector<int>()); res[0].push_back(1); for(int i=1;i<numRows;i++) { res[i].push_back(1); for(int j=1;j<i;j++) res[i].push_back(res[i-1][j-1]+res[i-1][j]); res[i].push_back(1); } return res; }