#include <iostream>
#include <fstream>
#include <string>
using namespace std;
int main()
{ifstream f("text.in");
ofstream g("text.out");
char s[256];
unsigned i,n=0,m=0;
f.get(s,256);
for(i=0;i<strlen(s);i++)
	{if(s[i]<='z' && 'a'<=s[i] || 'A'<=s[i] && s[i]<='Z')
		n=n+1;
		if(s[i]==' ')
			m=m+1;
	       if(s[i]=='-')
		if((s[i-1]<='z'&& 'a'<=s[i-1] || 'A'<=s[i-1] && 'Z'<=s[i-1])&&(s[i+1]<='z'&& 'a'<=s[i+1] || 'A'<=s[i+1] && 'Z'<=s[i+1]))
			m=m+1;}
g<<n/m;}