{
	char S[101]; char* t = "cww";
	rd(S); int n = strlen(S);
	ll ans = ll_inf;
	rep(i, n) {
		ll now = -1;
		int po = 0;
		rep(j, i, n) {
			if(S[j] == t[po]) po ++;
			if(po == 3) now = j - i + 1, break;
		}
		if(now != -1) ans <?= now;
	}
	if(ans == ll_inf) wt(-1);
	else wt(ans);	
}