
At one of the contests at the Petrozavodsk Training Camp, players of 
the Psych Up team quickly found the simple problem and Fedya sat at the 
computer. The solution was ready in five minutes. Without spending time 
for testing, Fedya submitted it and in a few seconds got Time Limit 
Exceeded. 
Fedya crumpled the problem statement and left the room slamming the 
door behind him. Things were going the wrong way and he needed to wind 
down. On his way to the restroom Fedya heard a conversation of the contest 
authors. Pasha was discussing with his friend the solution of the problem 
for which Fedya had got TLE. Fedya could only discern the word 
“eigenvalues.” 
Fedya thought about it and decided that he, for sure, had his eigenvalues. 
For example, the date of birth, the number of his apartment, the mark he 
had got at the latest exam, or the number of travels to contests. But they 
had a team contest, so what was their team's eigenvalue? Of course, a 
number was a team's eigenvalue if it was an eigenvalue for each of its 
players. With these joyful thoughts Fedya returned to the contest room. 
Input
The input data consist of three blocks two lines each. The first line of 
each block contains the number n of a player's eigenvalues (1 ≤ n ≤ 4 000). In the second line you are given n distinct integers in ascending order, which are the eigenvalues. All the eigenvalues are 
positive integers not exceeding 109. 
Output
Output the number of eigenvalues of the Psych Up team.
Sample
| input | output | 
|---|
| 5
13 20 22 43 146
4
13 22 43 146
5
13 43 67 89 146
 | 3
 | 
Problem Author: Denis Mukhametianov
Problem Source: Ural Regional School Programming Contest 2011