#include <bits/stdc++.h> 

using i64 = long long; 
using u64 = unsigned long long; 
using u32 = unsigned; 

using u128 = unsigned __int128; 
using i128 = __int128; 

void solve() {
	std::string s; std::cin >> s;
	int N = s.size();
	int a = -1;
	bool ok = false;
	for(int i = 0; i < N; i ++) {
		if(s[i] == 'c') {
			ok = true;
			a = i;
		}
	}
	if(!ok) {
		std::cout << -1;
		return;
	}
	int x = 0;
	for(int i = a; i < N; i ++) {
		if(s[i] == 'w') x ++;
		if(x == 2) {
			std::cout << i - a + 1;
			return;
		}
	}
	std::cout << -1;
} 

int main() { 
	std::ios::sync_with_stdio(false); 
	std::cin.tie(nullptr); 

	int T = 1; 
	//std::cin >> T; 

	while (T--) { 
		solve(); 
	} 
	return 0; 
}