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: Accepted)

#include <stdio.h>
int main(void){
	int i=0,checker=0;
	char st[11],ri[11],ng[11];
	scanf("%s %s %s",st,ri,ng);
	while(1==1){
		if(st[i]!='\0'){
			i++;
		}else{
			i--;
			break;
		}
	}
	if(st[i]==ri[0]){
		checker++;
	}
	i=0;
	while(1==1){
		if(ri[i]!='\0'){
			i++;
		}else{
			i--;
			break;
		}
	}
	if(ri[i]==ng[0]){
		checker++;
	}
	if(checker==2){
		printf("YES");
	}else{
		printf("NO");
	}
	return 0;
}