Problem A
Blackthorn
Blackthorn is a plant that grows in abundance in the fields around Stockholm. They form huge maze-like bushes that are home to many animals, and sometimes humans. This time of year (in early May), the blackthorn bushes are covered in beautiful white flowers. Go to the fields near Lill-Jansskogen after the contest and see for yourself!
The word blackthorn is also special because it contains kth as a substring. This means that the letters kth appears consecutively in the word. In this problem, you are given a word, and your task is to decide if it contains kth as a substring.
Input
The input consists of a string $s$ of length between $3$ and $100$. This string only consists of lowercase letters “a”-“z”.
Output
If $s$ contains kth as a substring, print “yes”. Otherwise, print “no”.
| Sample Input 1 | Sample Output 1 |
|---|---|
blackthorn |
yes |
| Sample Input 2 | Sample Output 2 |
|---|---|
kitakyushu |
no |
