Pascal's Triangle 打印数字三角形

Pascal's Triangle

 

Given numRows, generate the first numRows of Pascal's triangle.

For example, given numRows = 5,
Return

[     [1],    [1,1],   [1,2,1],  [1,3,3,1], [1,4,6,4,1]]

class Solution {public:    vector<vector<int> > generate(int numRows) {                vector<vector<int>> ans ;        int i,j;        for(i=0;i<numRows;i++)        {            vector<int> cur;            for(j=0;j<=i;j++)            {                if(j==0||j==i)                    cur.push_back(1);                else                    cur.push_back(ans[i-1][j-1]+ans[i-1][j]);            }            ans.push_back(cur);        }        return ans;    }};