#include <iostream>
#include <algorithm>
#include <functional>
#include <string>
using namespace std;

int main(){
	char a;
	int ren = 0;
	int max = 0;
	
	for(int i=0; i<14; i++){
		cin >> a;
		if(a == 'o'){
			ren ++;
		}else{
			if(ren > max){
				max = ren;
			}
			ren = 0;
		}
	}
	
	if(ren > max){
		max = ren;
	}
	cout << max << endl;
	return 0;
}