Given an array A, of N elements. Sort the array using mergesort algorithm.
Input Format
A single integer, N, denoting the number of elements in array. Next line contains N integers, denoting the elements of array.
Constraints
1<=N<=2*10^5 |Ai|<=10^9
solution link: https://ide.codingblocks.com/s/278959
showing run error in all test cases
