import java.util.Scanner;

public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        String s = sc.next();

        if (s.contains("RRR")) System.out.println(3);
        else if (s.contains("RR")) System.out.println(2);
        else if (s.contains("R")) System.out.println(1);
        else System.out.println(0);
    }
} import java.util.Scanner; Scanner java.util public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        String s = sc.next();

        if (s.contains("RRR")) System.out.println(3);
        else if (s.contains("RR")) System.out.println(2);
        else if (s.contains("R")) System.out.println(1);
        else System.out.println(0);
    }
} Main public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        String s = sc.next();

        if (s.contains("RRR")) System.out.println(3);
        else if (s.contains("RR")) System.out.println(2);
        else if (s.contains("R")) System.out.println(1);
        else System.out.println(0);
    } main {
        Scanner sc = new Scanner(System.in);
        String s = sc.next();

        if (s.contains("RRR")) System.out.println(3);
        else if (s.contains("RR")) System.out.println(2);
        else if (s.contains("R")) System.out.println(1);
        else System.out.println(0);
    } Scanner sc = new Scanner(System.in); sc new Scanner(System.in) String s = sc.next(); s sc.next() sc.next sc if (s.contains("RRR")) System.out.println(3);
        else if (s.contains("RR")) System.out.println(2);
        else if (s.contains("R")) System.out.println(1);
        else System.out.println(0); s.contains("RRR") s.contains s "RRR" System.out.println(3) System.out.println System.out System System.out 3 if (s.contains("RR")) System.out.println(2);
        else if (s.contains("R")) System.out.println(1);
        else System.out.println(0); s.contains("RR") s.contains s "RR" System.out.println(2) System.out.println System.out System System.out 2 if (s.contains("R")) System.out.println(1);
        else System.out.println(0); s.contains("R") s.contains s "R" System.out.println(1) System.out.println System.out System System.out 1 System.out.println(0) System.out.println System.out System System.out 0 String[] args args public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        String s = sc.next();

        if (s.contains("RRR")) System.out.println(3);
        else if (s.contains("RR")) System.out.println(2);
        else if (s.contains("R")) System.out.println(1);
        else System.out.println(0);
    }
} public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        String s = sc.next();

        if (s.contains("RRR")) System.out.println(3);
        else if (s.contains("RR")) System.out.println(2);
        else if (s.contains("R")) System.out.println(1);
        else System.out.println(0);
    }
} Main
import java.util.Scanner;

public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        String s = sc.next();

        if (s.contains("RRR")) System.out.println(3);
        else if (s.contains("RR")) System.out.println(2);
        else if (s.contains("R")) System.out.println(1);
        else System.out.println(0);
    }
}
