118. Pascal's Triangle

就一句话，注意下表

class Solution {public:    vector<vector<int>> generate(int numRows) {        vector<vector<int>>ve;        vector<int>vec;        if(numRows == 0) return ve;        vec.push_back(1);        ve.push_back(vec);        if(numRows == 1) return ve;        vec.push_back(1);        ve.push_back(vec);        for(int i = 3; i <= numRows; ++ i){            vec.clear();            vec.push_back(1);            for(int j = 2; j <= i - 1; ++ j){                vec.push_back(ve[i - 1 - 1][j - 1 - 1] + ve[i - 1 - 1][j - 1]);            }            vec.push_back(1);            ve.push_back(vec);        }        return ve;    }};