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 Go (1.6) (judge verdict: Accepted)

package main

import (
  "bufio"
  "os"
  "strings"
  "fmt"
)

func main() {
  sc := bufio.NewScanner(os.Stdin)
  sc.Scan()
  strArr := strings.Split(sc.Text(), " ")
  if strArr[0][len(strArr[0])-1] == strArr[1][0] && strArr[1][len(strArr[1])-1] == strArr[2][0] {
    fmt.Println("YES")
  } else {
    fmt.Println("NO")
  }
}