use v6;

my @str = get().chomp.split('');

my $w = 0;
my $long = 0;
loop (my $i = 1; $i < @str.elems - 1; $i++) {
	if @str[$i] eq 'c' {
		loop (my $j = $i; $j < @str.elems - 1; $j++) {
			if @str[$j] eq 'w' {
				if $w == 0 {
					$w++;
				} elsif $w == 1 {
					if $long == 0 {
						$long = $j - $i + 1;
					} elsif $j - $i + 1 < $long {
						$long = $j - $i + 1;
					}
					$w = 0;
					last;
				}
			}
		}
	}
}

if $long == 0 {
	say -1;
} else {
	say $long;
}
exit;