Problem:
Score : 100 points

Problem Statement

You are given three strings A, B and C. Check whether they form a word chain.

More formally, determine whether both of the following are true:

The last character in A and the initial character in B are the same.

The last character in B and the initial character in C are the same.

If both are true, print YES. Otherwise, print NO.

Constraints

A, B and C are all composed of lowercase English letters (a - z).

1 ≤ |A|, |B|, |C| ≤ 10, where |A|, |B| and |C| are the lengths of A, B and C, respectively.

Input

Input is given from Standard Input in the following format:

A B C

Output

Print YES or NO.

Sample Input 1

rng gorilla apple

Sample Output 1

YES

They form a word chain.

Sample Input 2

yakiniku unagi sushi

Sample Output 2

NO

A and B form a word chain, but B and C do not.

Sample Input 3

a a a

Sample Output 3

YES

Sample Input 4

aaaaaaaaab aaaaaaaaaa aaaaaaaaab

Sample Output 4

NO

Solution in PHP7 (7.0.15) (judge verdict: Runtime Error)

<?php

$str = trim(fgets(STDIN));
$array = explode(' ', $str);
$A = (int)$array[0];
$B = (int)$array[1];
$C = (int)$array[2];

$array = [];
for($i = 1; $i < 100; $i++){
    $Anum = $A*$i;
    $sub = $Anum % $B;
    if (!in_array($sub, $array)) {
        $array[] = $sub;
        if ($C == $sub) {
            echo "YES";
            exit;
        }
    } else {
        break;
    }
}
echo "NO";