#include<iostream>
#include<string>
#include<string.h>
#include<algorithm>
#include<stdio.h>
#include<cmath>
#include<vector>
#include<utility>
#include<stack>
#include<queue>
#include<list>
#include<bitset>
#include<functional>

#define FOR(i, a, b) for(int i=(a);i<=(b);i++)
#define RFOR(i, a, b) for(int i=(a);i>=(b);i--)
#define MOD 1000000007
#define INF 1000000000
#define PI 3.14159265358979

using namespace std;
typedef pair<int, int> P;

int main(void) {
	string s;
	int p, q;

	cin >> s;
	FOR(i, 0, s.size() - 1) {
		if (s[i] == 'w') {
			p = i;
			q = s.size() - i;
			break;
		}
	}

	p -= 1;
	if (p < q) {
		cout << p << endl;
	}
	else {
		cout << q << endl;
	}

	return 0;
}