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 (GCC 5.4.1) (judge verdict: Wrong Answer)

#include<stdio.h>
#include<string.h>
int main()
{
     char a1[10],a2[10],a3[10] ;
	 scanf("%s %s %s",a1,a2,a3);
     int l1,l2,l3;
     l1=strlen(a1);
     l2=strlen(a2);
     l3=strlen(a3);
     char x,y1,y2,z;
     x=a1[l1-1];
     y1=a2[0];
     y2=a2[l2-1];
     z=a3[0];
     if(x==y1&&y2==z)printf("YES\nThey form a word chain.");
     if(x!=y1)printf("NO");
     if(x==y1&&y2!=z)printf("NO\nA and B form a word chain, but B and C do not.");
    
     
     
	 return 0;    
}