#include <iostream>
#include <string.h>
using namespace std;
int main()
{
	int i,j,lt=0,cuvant=0;
	char n[1000000];
	freopen("text.in","r",stdin);
	freopen("text.out","w",stdout);

	fgets(n,1000000,stdin);
	strcat(n, "#");
	for(i=0;i<strlen(n);i++){
		if((n[i]>='a' && n[i]<='z')|| (n[i]>='A' && n[i]<='Z'  )){
			for(j=i;(n[j]>='a' && n[j]<='z')|| (n[j]>='A' && n[j]<='Z'  );j++);
			cuvant++;
			lt=lt+(j-i);
			i = j + 1;
			
		}
	}
	if (cuvant == 0) cout << 0;
	else cout<<lt/cuvant;
	return 0;

}