Update solution to problem 60. It still fails almost of the test cases on hackerrank. And there's still run time error for large N. Should ask the hackerrank admin for help.
Update solution to problem 60. It still fails almost of the test cases on
hackerrank. And there's still run time error for large N. Should ask the
hackerrank admin for help.

advancedxy/hackerrank,advancedxy/hackerrank,advancedxy/hackerrank