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){
  char s[35];
  char x, y, z, w;
  fgets(s, 35, stdin);
  int c = 0;
  int f = 0;
  while(f != 2){
    if(s[c] == ' ' && f == 1) {
      z = s[c - 1];
      w = s[c + 1];
      f++;
    }
    if(s[c] == ' ' && f == 0) {
      x = s[c - 1];
      y = s[c + 1];
      f++;
    }
    c++;
  }
  if(x == y && z == w) printf("YES\n");
  else printf("NO\n");
  return 0;
}