#include<stdio.h>
#include<string.h>
int s,poz,i,cuv;
char c,cc;
int main()
{
	freopen("text.in","r",stdin);
	freopen("text.out","w",stdout);
	while(scanf("%c",&c)!=EOF)
	{
		cc=c;
		if(c<'A')
		{
			s+=poz;
			cuv++;
			poz=0;
			while(c<'A'&&scanf("%c",&c)!=EOF)
				scanf("%c",&c);
			i--;
		}
		poz++;
	}
	printf("%d",s/cuv);
	return 0;
}