Given a non-negative integer numRows, generate the first numRows of Pascal's triangle.
In Pascal's triangle, each number is the sum of the two numbers directly above it.
Example:
Input: 5 Output: [ [1], [1,1], [1,2,1], [1,3,3,1], [1,4,6,4,1] ]
1 class Solution { 2 public: 3 vector<vector<int>> generate(int numRows) { 4 vector<vector<int>> res ; 5 if(numRows<=0) return res; 6 vector<int> t(1,1); 7 res.push_back(t); 8 for(int r = 2;r<=numRows;r++){ 9 vector<int> temp(r,1); 10 for(int i = 1;i<r-1;i++) 11 temp[i] = res[r-2][i-1]+res[r-2][i]; 12 res.push_back(temp); 13 } 14 return res; 15 } 16 };