#include <stdio.h>

int main()
{
	char C;
	int holiday = 0, holidaymax = 0;

	for (int i = 0; i < 16; i++)
	{
		scanf("%c",&C);

		if (C == '\n')
		{
			continue;
		}

		if (C == 'o')
		{
			holiday++;

			if (holiday > holidaymax)
			{
				holidaymax = holiday;
			}

			continue;
		}

		holiday = 0;
	}

	printf("%d", holidaymax);

	return 0;
}