import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;

public class Hash {

    public static String sha256(String input) {

        try {
            MessageDigest md = MessageDigest.getInstance("SHA-256");
            byte[] hash = md.digest(input.getBytes(java.nio.charset.StandardCharsets.UTF_8));
            StringBuilder hexString = new StringBuilder();
            for (byte b : hash) {
                String hex = Integer.toHexString(0xff & b);
                if (hex.length() == 1) hexString.append('0');
                hexString.append(hex);
            }
            return hexString.toString();
        } catch (NoSuchAlgorithmException e) {
            throw new RuntimeException("SHA-256 algorithm not found", e);
        }
    }

    public static String evilCode(String input){
        return sha256(input).substring(0, 15);
    }
}