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: Runtime Error)

import java.util.Scanner;


public class Main {

    public static void main(String[] args) {

    	Main main=new Main();

    	main.run();

    }

    void run() {

    	Scanner sc=new Scanner(System.in);

    	String a=sc.next();
    	String b=sc.next();
    	String c=sc.next();
    	
    	boolean first=a.substring(a.length(),a.length()+1).equals(b.substring(0, 1));
    	boolean last=b.substring(b.length(),b.length()+1).equals(c.substring(0, 1));
    	
    	if(first && last) {
    		System.out.println("YES");
    	}else {
    		System.out.println("NO");
    	}
    }
}