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 9.2.1) (judge verdict: Wrong Answer)

#include <stdio.h>

int main(){
  char a[10];
  char b[10];
  char c[10];
  int a_pos=0;
  int b_pos=0;
  int i;
  
  scanf("%s%s%s",a,b,c);
  for(i=0;a[i]!='\0';i++){
    a_pos++;
  }
  for(i=0;b[i]!='\0';i++){
    b_pos++;
  }
  
  if((a[a_pos-1]==b[0])&&(b[b_pos-1]==c[0])){
    printf("YES\n");
  }
  else{
    printf("NO\n");
  }
  
  return 0;
}