#include <stdio.h>
#include <algorithm>
#include <iostream>
#include <string>
#include <vector>
#include <functional>
#include <map>
#include <iomanip>
#include <math.h> 
#include <stack>
#include <queue>
#include <bitset>
#include <cstdlib>
#include <tuple>
#include <cctype>
#include <ctype.h>
#include <set>
#include <sstream>

using namespace std;


int main() {
	int i, j, k;
	string s;

	cin >> s;

	int minn = 99999999;

	for (i = s.length()-1; i >= 0; i--) {
		if (s[i] == 'w') {

			for (j = i - 1; j >= 0; j--) {
				
				if (s[j] == 'w') {
					//bool flag = false;
					for (k = j-1; k >= 0; k--) {
						if (s[k] == 'c') {
							minn = min(minn, i - k + 1);
						//	flag = true;
							break;
						}
					}

				}
			
			}
			
		}
	}

	if (minn < 999999) {
		cout << minn << endl;
	}
	else {
		cout << -1 << endl;
	}



	getchar();
	getchar();
	return 0;
}