判断字符串的最大重复的项目的一个算法，怎么利用C语言的程序编写的过程去实现的？

Question

Problem Description
Here you have a set of strings. A dominator is a string of the set dominating all strings else. The string S is dominated by T if S is a substring of T.

Input
The input contains several test cases and the first line provides the total number of cases.
For each test case, the first line contains an integer N indicating the size of the set.
Each of the following N lines describes a string of the set in lowercase.
The total length of strings in each case has the limit of 100000.
The limit is 30MB for the input file.

Output
For each test case, output a dominator if exist, or No if not.

Sample Input
3
10
you
better
worse
richer
poorer
sickness
health
death
faithfulness
youbemyweddedwifebetterworsericherpoorersicknesshealthtilldeathdouspartandpledgeyoumyfaithfulness
5
abc
cde
abcde
abcde
bcde
3
aaaaa
aaaab
aaaac

Sample Output
youbemyweddedwifebetterworsericherpoorersicknesshealthtilldeathdouspartandpledgeyoumyfaithfulness
abcde
No

Answer 1

这个题简单啊，因为dominator 包括所有子字符串，那么它一定是最长的，然后依次在这个最长的字符里查其它字符串是否包含在里边，如果都在里边，那么久找到了dominator ，把它打印出来，否则打印NO.