Check If two string are anagrammatic, this means, the if you can get the second string by rearrenge the Characters of one string. 

For Example:

1) georgebush

2) hebugsgore

Now, implementing this would be way to simple, lets add a complexity here,

You need to do it in less then O(nlogn) time. 

If you use any sort function, the complexity would be nlogn, hence not an acceptable solution.