Problem 4

Given a list of N (1 <= N <= 50000) integers. You are required to compute the number of pairs of indexes whose values are the same, and also the maximum distance between two indexes with equal values. N will be given in the first line of the input. N lines follow, each one with one integer from the list. If no identical pairs are found, print NA, otherwise print a single line with two integers, the number of identical pairs, and the maximum distance between indexes with equal values.

Case 1:

For the input provided as follows:

5
1
3
1
6
3

Output of the program will be:

2 3

Case 2:

For the input provided as follows:

6
1
2
3
4
5
6

Output of the program will be:

NA