#include<stdio.h>
#include<string.h>
using namespace std;
FILE *fi,*fo;
int i,lit,nrcuv;
char A[10000];
char *pch;
int main()
{
	fi=fopen("text.in","r");
	fo=fopen("text.out","w");
	for(i=0; i<10000; i++)
	{
		fscanf(fi,"%c",&A[i]);
	}
	pch=strtok(A," .?!,-");
	while(pch!=NULL)
	{
		nrcuv++;
		lit=lit+strlen(pch);
		pch=strtok(NULL," .?!,-");
	}
	fprintf(fo,"%d",lit/nrcuv);
	fclose(fi);
	fclose(fo);
	return 0;
}