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 Java8 (OpenJDK 1.8.0) (judge verdict: Accepted)

import java.util.Comparator;
import java.util.Scanner;

class Main{


	static int[][] map ;
	static long INF =Long.MAX_VALUE/2;
	static int n,m ;
	static	long[] dis;

	public static void main(String[] args) {


		Scanner sc = new Scanner(System.in);			//文字の入力
		String a = sc.next();
		String b = sc.next();
		String c = sc.next();

		if(a.charAt(a.length()-1) == b.charAt(0) && b.charAt(b.length()-1) == c.charAt(0)){
			System.out.println("YES");
		}else{
			System.out.println("NO");

		}
		
		
	}
}





class MyComparator implements Comparator {

	public int compare(Object obj1, Object obj2) {

		int num1 = (int)obj1;
		int num2 = (int)obj2;

		if(num1 < num2) {
			return 1;
		} else if(num1 > num2) {
			return -1;
		} else{
			return 0;
		}
	}
}