E. Permutation
time limit per test
1 second
memory limit per test
256 megabytes
input
standard input
output
standard output

This problem's statement is secret :

"uoY'er viegn na raayr fo itnsereg, dnif hte cesdno tslmlesa etelmne fo het rraya nad irtpn ti".

Input

In the first line of input, You'll be given $$$n(2 \le n \le 100)$$$.

In the second line of input, You'll be given an array $$$a(2 \le a_{i} \le 100)$$$.

Output

Print the answer.

Example
Input
8
2 3 5 7 13 17 19 23
Output
3