import java.io.*;

class Process {
    private String[] S;

    Process(String[] S) {
        this.S = S;
    }

    int getResult() {
        String days = S[0] + S[1];

        int holidayCount = 0;
        int maxHolidayCount = 0;
        for(int i = 0; i < days.length(); i++) {
            if(days.charAt(i) == 'o') {
                holidayCount++;
            } else {
                if(holidayCount > maxHolidayCount) {
                    maxHolidayCount = holidayCount;
                }

                holidayCount = 0;
            }
        }

        if(holidayCount > maxHolidayCount) {
            maxHolidayCount = holidayCount;
        }

        return maxHolidayCount;
    }
}

public class Main {
    public static void main(String[] args) throws IOException {
        var bufferedReader = new BufferedReader(new InputStreamReader(System.in));
        var printWriter    = new PrintWriter(new BufferedWriter(new OutputStreamWriter(System.out)));

        // 入力
        var S = new String[2];
        for(int i = 0; i < 2; i++) {
            S[i] = bufferedReader.readLine().trim();
        }

        // 処理および出力
        printWriter.println((new Process(S)).getResult());

        bufferedReader.close();
        printWriter.close();
    }
}