We have a list of strings . All strings have length and consist only of characters A, B, C and D. Let us define the distance between two strings and as the number of indices , where the strings have different characters (). We know that the list of strings contains precisely one special string that has distance to all other strings. Note that there might be other pairs of strings with a distance of . We are experiencing problems finding this special string, so please write a program to help us out.
输入格式
The first line contains space-separated integers , and . Strings are given in the following lines.
输出格式
Output the index of the special string. Strings are numbered from 1 to as given in the input.
