Repeated String

import java.io.*;
import java.math.*;
import java.security.*;
import java.text.*;
import java.util.*;
import java.util.concurrent.*;
import java.util.regex.*;

public class Solution {

    static long repeatedString(String s, long n) {
        int aInInputString = 0;
        for (int i = 0; i < s.length(); i++)
        if(s.charAt(i) == 'a') aInInputString++;
        long completeRepeats = n / s.length();

        long rem = n % s.length();
        int aInRemaining = 0;
        for (int i = 0; i < rem; i++)
        if(s.charAt(i) == 'a') aInRemaining++;

        return completeRepeats*aInInputString + aInRemaining;
    }

    private static final Scanner scanner = new Scanner(System.in);

    public static void main(String[] args) throws IOException {
        BufferedWriter bufferedWriter = new BufferedWriter(new FileWriter(System.getenv("OUTPUT_PATH")));

        String s = scanner.nextLine();

        long n = scanner.nextLong();
        scanner.skip("(\r\n|[\n\r\u2028\u2029\u0085])?");

        long result = repeatedString(s, n);

        bufferedWriter.write(String.valueOf(result));
        bufferedWriter.newLine();

        bufferedWriter.close();

        scanner.close();
    }
}