[LeetCode]Pascal's Triangle

原题链接：http://oj.leetcode.com/problems/pascals-triangle/

题意描述：

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]

]

题解：

　　两端为1，中间为v[i][j] = v[i-1][j-1]+v[i-1][j];

 1 class Solution {

 2 public:

 3     vector<vector<int> > generate(int numRows) {

 4         vector <vector<int>> v(numRows); 

 5         for(int i=0;i<numRows;i++)

 6             v[i].resize(i+1);

 7         

 8         for(int i=0; i<numRows; i++){

 9             for(int j=0; j<i+1; j++){

10                 if(j==0 || j==i)

11                     v[i][j] = 1;

12                 else

13                     v[i][j] = v[i-1][j-1]+v[i-1][j];

14             }

15         }

16         

17         return v;

18     }

19 };

View Code