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>
#include <string.h>

char a[10] = {};
char b[10] = {};
char c[10] = {};

int main()
{
	int a_length, b_length, c_length;
	char a_first, a_last;
	char b_first, b_last;
	char c_first, c_last;
	scanf("%s %s %s", a, b, c);
	//get length
	a_length = strlen(a);
	b_length = strlen(b);
	c_length = strlen(c);
	//get first and last
	a_first = a[0];
	a_last = a[a_length-1];
	b_first = b[0];
	b_last = b[b_length-1];
	c_first = c[0];
	c_last = c[c_length-1];
	//check first = last
	if (a_last == b_first && b_last == c_first)
	{
		printf("YES");
	}
	else
	{
		printf("NO");
	}
	return 0;
}