#include <regex>
#include <string>
#include <iostream>

int
chiwawa(std::string const& input, int start = 0){
	auto c = input.find('c', start);
	if( c == std::string::npos ) return -1;

	auto w = input.find('w', c);
	if( w == std::string::npos ) return -1;

	auto w2 = input.find('w', w + 1);
	if( w2 == std::string::npos ) return -1;

	int result = w2 - c + 1;
	auto next   = chiwawa(input, c + 1);
	return (next == -1 || result <= next) ? result : next;
}

int
main(){
	std::string str;
 	std::cin >> str;
	std::cout << chiwawa(str) << std::endl;
	
	return 0;
}