[Leetcode] Pascal's Triangle II

 1 public class Solution {
 2     public List<Integer> getRow(int rowIndex) {
 3         List<Integer> result = new ArrayList<Integer>();
 4         if (rowIndex < 0)
 5             return result;
 6         
 7         for(int i=0;i<rowIndex;++i){
 8             int a=getNumber(rowIndex,i);    
 9             result.add(a);
10         }
11         result.add(1);
12         return result;
13     }
14 
15     private int getNumber(int rowIndex, int i) {
16         // TODO Auto-generated method stub
17         long result=1l;
18         for(int j=0;j<i;++j){
19             result*=rowIndex--;
20         }
21         
22         for(int j=i;j>0;--j){
23             result/=j;
24         }
25         return (int) result;
26     }
27 }