//No.369 足し間違い

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


namespace
{
int WW( const char *S )
{
int i;
int iCnt;
char C;

	iCnt = 0;

	i = 0;
	C = S[ i ];
	while( C != '\0' )
	{
		if( C == 'w' )
		{
			iCnt++;
			if( iCnt >= 2 ) return i;
		}

		i++;
		C = S[ i ];
	}

	return - 1;
}

}

int main()
{
int i;
int j;
int iMin;
char S[ 110 ];
char C;

	cin >> S;

	iMin = 300;

	i = 0;
	C = S[ i ];
	while( C != '\0' )
	{
		if( C == 'c' )
		{
			j = WW( S + i + 1 );
			if( j < 0 ) break;
			if( j == 1 )
			{
				iMin = 3;

				break;
			}
			if( iMin > j + 2 ) iMin = j + 2;
		}

		i++;
		C = S[ i ];
	}

	if( iMin == 300 )
		cout << - 1 << endl;
	else
		cout << iMin << endl;

	return 0;
}