#include <bits/stdc++.h>
using namespace std;

int main()
{
int i;
long long iPos;
long long i2;
char S[ 50 ];
char C;

	if( ! ( cin >> S ) )
	{
		cout << 1 << endl;

		return 0;
	}

	iPos = 0;
	i2 = 1;
	i = 0;
	C = S[ i ];
	while( C != '\0' )
	{
		if( C == 'L' )
			iPos *= 2;
		else
			iPos = iPos * 2 + 1;

		i2 *= 2;
		i++;
		C = S[ i ];
	}

	cout << i2 + iPos << endl;

	return 0;
}