import java.util.Scanner;

public class Main {

    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        String s = sc.next();
        int sum = 0;
        int max = 0;
        for (int i = 0; i < s.length(); i++) {
            char ch = s.charAt(i);
            if (ch == 'R') {
                sum++;
                max = Math.max(max, sum);
            } else {
                sum = 0;
            }
        }
        System.out.println(max);
    }
} 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();
        int sum = 0;
        int max = 0;
        for (int i = 0; i < s.length(); i++) {
            char ch = s.charAt(i);
            if (ch == 'R') {
                sum++;
                max = Math.max(max, sum);
            } else {
                sum = 0;
            }
        }
        System.out.println(max);
    }
} Main public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        String s = sc.next();
        int sum = 0;
        int max = 0;
        for (int i = 0; i < s.length(); i++) {
            char ch = s.charAt(i);
            if (ch == 'R') {
                sum++;
                max = Math.max(max, sum);
            } else {
                sum = 0;
            }
        }
        System.out.println(max);
    } main {
        Scanner sc = new Scanner(System.in);
        String s = sc.next();
        int sum = 0;
        int max = 0;
        for (int i = 0; i < s.length(); i++) {
            char ch = s.charAt(i);
            if (ch == 'R') {
                sum++;
                max = Math.max(max, sum);
            } else {
                sum = 0;
            }
        }
        System.out.println(max);
    } Scanner sc = new Scanner(System.in); sc new Scanner(System.in) String s = sc.next(); s sc.next() sc.next sc int sum = 0; sum 0 int max = 0; max 0 for (int i = 0; i < s.length(); i++) {
            char ch = s.charAt(i);
            if (ch == 'R') {
                sum++;
                max = Math.max(max, sum);
            } else {
                sum = 0;
            }
        } int i = 0; int i = 0; i 0 i < s.length() i s.length() s.length s i++ i++ i {
            char ch = s.charAt(i);
            if (ch == 'R') {
                sum++;
                max = Math.max(max, sum);
            } else {
                sum = 0;
            }
        } {
            char ch = s.charAt(i);
            if (ch == 'R') {
                sum++;
                max = Math.max(max, sum);
            } else {
                sum = 0;
            }
        } char ch = s.charAt(i); ch s.charAt(i) s.charAt s i if (ch == 'R') {
                sum++;
                max = Math.max(max, sum);
            } else {
                sum = 0;
            } ch == 'R' ch 'R' {
                sum++;
                max = Math.max(max, sum);
            } sum++ sum max = Math.max(max, sum) max Math.max(max, sum) Math.max Math max sum {
                sum = 0;
            } sum = 0 sum 0 System.out.println(max) System.out.println System.out System System.out max String[] args args public class Main {

    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        String s = sc.next();
        int sum = 0;
        int max = 0;
        for (int i = 0; i < s.length(); i++) {
            char ch = s.charAt(i);
            if (ch == 'R') {
                sum++;
                max = Math.max(max, sum);
            } else {
                sum = 0;
            }
        }
        System.out.println(max);
    }
} public class Main {

    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        String s = sc.next();
        int sum = 0;
        int max = 0;
        for (int i = 0; i < s.length(); i++) {
            char ch = s.charAt(i);
            if (ch == 'R') {
                sum++;
                max = Math.max(max, sum);
            } else {
                sum = 0;
            }
        }
        System.out.println(max);
    }
} Main
import java.util.Scanner;

public class Main {

    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        String s = sc.next();
        int sum = 0;
        int max = 0;
        for (int i = 0; i < s.length(); i++) {
            char ch = s.charAt(i);
            if (ch == 'R') {
                sum++;
                max = Math.max(max, sum);
            } else {
                sum = 0;
            }
        }
        System.out.println(max);
    }
}
