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 C++14 (GCC 5.4.1) (judge verdict: Wrong Answer)

#include"iostream"
using namespace std;

int main() {
	char a[9], b[9], c[9];
	int d,ai,bi,ci;

	cin >> a;
	cin >> b;
	cin >> c;

	for (d = 0; d < 10; d++) {
		if (a[d] == '\0'){
			ai = d - 1;
		}
	}
	for (d = 0; d < 10; d++) {
		if (b[d] == '\0') {
			bi = d - 1;
		}
	}

	if (a[ai] != b[0]) {
		cout << "NO" << endl;
	}
	else if (b[bi] != c[0]) {
		cout << "NO" << endl;
	}
	else {
		cout << "YES" << endl;
	}

	return 0;
}