# LeetCode – Factor Combinations (Java)

Numbers can be regarded as product of its factors. For example,

8 = 2 x 2 x 2; = 2 x 4.

Write a function that takes an integer n and return all possible combinations of its factors.

Note:

You may assume that n is always positive.

Factors should be greater than 1 and less than n.

**Java Solution**

public List<List<Integer>> getFactors(int n) { List<List<Integer>> result = new ArrayList<List<Integer>>(); List<Integer> list = new ArrayList<Integer>(); helper(2, 1, n, result, list); return result; } public void helper(int start, int product, int n, List<List<Integer>> result, List<Integer> curr){ if(start>n || product > n ) return ; if(product==n) { ArrayList<Integer> t = new ArrayList<Integer>(curr); result.add(t); return; } for(int i=start; i<n; i++){ if(i*product>n) break; if(n%i==0){ curr.add(i); helper(i, i*product, n, result, curr); curr.remove(curr.size()-1); } } } |

<pre><code> String foo = "bar"; </code></pre>