#include <stdio.h>

int main(void)
{
	char day[14];
	int i;
	int tmp = 0;
	int max = 0;

	scanf("%s", day);

	for ( i = 0; i < 14; i++ ) {
		if ( day[i] == 'o' )	{
			tmp++;
		} else {
			if ( tmp > max ) {
				max = tmp;
			}
			tmp = 0;
		}
	}
	printf("%d\n", max);
	return 0;
}