Saturday, April 12, 2014

Combinations (Java)

Given two integers n and k, return all possible combinations of k numbers out of 1 ... n.
For example,
If n = 4 and k = 2, a solution is:

Solution: a classical DFS problem, pay attention to the format of solve this question which can be apply to many other DFS problems

Saturday, April 5, 2014

Remove Nth Node From End of List (Java)

Given a linked list, remove the nth node from the end of list and return its head.
For example,
   Given linked list: 1->2->3->4->5, and n = 2.

   After removing the second node from the end, the linked list becomes 1->2->3->5.
Given n will always be valid.
Try to do this in one pass.