Even Chef have Friends!

Chef decided to find the connections with all of his friends in an unnamed social network. He calls a user of the social network his friend if there is a common substring of the string “chef” and the nickname of that user with length ≥ 2.

Given a list of users of the social network, compute the number of Chef’s friends.

Input Format

The first line of the input contains a single integer N denoting the number of users in the social network.

N lines follow. Each of these lines contains a single string u denoting the nickname of one user.

Constraints

1 ≤ N ≤ 5,000
3 ≤ |u| ≤ 20

each character of each user’s nickname is either a lowercase English letter (‘a’-‘z’) or ’.’

the first character of each user’s nickname is a lowercase English letter.

Output Format

Print a single line containing one integer — the number of Chef’s friends.

Sample Input

4
gennady.korotkevich
kefaa
fhlasek
chemthan

Sample Output

3

Explanation

gennady.korotkevich is a friend to Chef because he has “ch” at the end of his nickname, which is also a substring of “chef” with length 2

The common substring with kefaa is “ef” and the common substring with chemthan is “che”

Solution in java

import java.util.Scanner;

class chefAndFriends {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int num_of_cases = sc.nextInt();
        int count = 0;
        while (num_of_cases-- > 0) {
            String s = sc.next();
            String chef = "chef";
            for (int i = 0; i < s.length() - 1; i++) {
                String sub = s.substring(i, i + 2);
                if (chef.contains(sub)) {
                    count++;
                    break;
                }
            }
        }
        System.out.println(count);
        sc.close();
    }
}