write a c# program that does the following:(basically checks if both strings have same elements then orders it alphabetically and prints it, please do everything in main)

reads two strings s and t, each on its own line. Each string will contain only lowercase letters. The program should print a string u such that

Some permutation of u is a subsequence of s.

Some permutation of u is a subsequence of t.

u is as long as possible.

A subsequence is not necessarily contiguous. If there is more than one longest possible u, print the one that comes first alphabetically.

Sample input:

watermelon summertime 

Output:

eemrt