#include<stdio.h>
int i, wcount, wletter,sum,j,result;
int main()
{
	char a;	
	FILE*f=fopen("text.in","r");
	FILE*g=fopen("text.out","w");
	while(!feof(f))
	{
		fscanf(f,"%c",&a);
		if(( a >='A' && a <='Z') || ( a >='a' && a <='z'))
			wletter++;
		else
			if(wletter!=0)
			{
				sum+=wletter;
				wcount++;
				wletter=0;
			}
	}
	if(wletter!=0)
	{
		sum+=wletter;
		wcount++;
	}
	if(wcount!=0)
		result=sum/wcount;
	else
		result=0;
	fprintf(g,"%d",result);
	fcloseall();

	return 0;
}