CF798B.Mike and strings

Mike has n strings _s_1, _s_2, ..., s__n each consisting of lowercase English letters. In one move he can choose a string s__i, erase the first character and append it to the end of the string. For example, if he has the string "coolmike", in one move he can transform it into the string "oolmikec".

Now Mike asks himself: what is minimal number of moves that he needs to do in order to make all the strings equal?

Mike 有 n 个字符串 _s_₁, _s_₂, ..., s__n，每个字符串均由小写英文字母组成。在一次操作中，他可以选择某个字符串 s__i，删除其首字符，并将该字符追加到该字符串末尾。例如，若他拥有字符串 "coolmike"，则通过一次操作可将其变为 "oolmikec"。

现在 Mike 想知道：他至少需要多少次操作，才能使所有字符串变得完全相同？

The first line contains integer n (1 ≤ n ≤ 50) — the number of strings.

This is followed by n lines which contain a string each. The i-th line corresponding to string s__i. Lengths of strings are equal. Lengths of each string is positive and don't exceed 50.

第一行包含一个整数 $n$（$1 \leq n \leq 50$）—— 字符串的数量。

接下来是 $n$ 行，每行包含一个字符串。第 $i$ 行对应字符串 $s_i$。所有字符串的长度相等，且每个字符串的长度为正整数，不超过 $50$。

Print the minimal number of moves Mike needs in order to make all the strings equal or print  - 1 if there is no solution.

输出 Mike 使所有字符串相等所需的最少操作次数；如果无解，则输出 $-1$。

In the first sample testcase the optimal scenario is to perform operations in such a way as to transform all strings into "zwoxz".

在第一个样例测试用例中，最优方案是执行操作，使得所有字符串都变为 "zwoxz"。