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 is_siritori(char f[10], char s[10])
{
  int i = 0;
  while(f[i])
  {
    i++;
  }
  i -= 1;
  if (f[i] != s[0])
  {
    printf("NO");
    return (0);
  }
  else
    return (1);
}

int main()
{
  char a[10],b[10],c[10];
  scanf("%s%s%s",&a,&b,&c);
  if (!(is_siritori(a,b)))
    return (0);
  if (!(is_siritori(b,c)))
    return(0);
  printf("YES");
    
}