#include<cstdio>
#include<cctype>

FILE *fin=fopen("text.in","r");
FILE *fout=fopen("text.out","w");

int s,k;
char c;

int main(){
	
	k=0;s=0;
	
	while(!feof(fin)){
		
		fscanf(fin,"%c",&c);
		while(!isalpha(c) && !feof(fin))
			fscanf(fin,"%c",&c);
		
		while(isalpha(c) && !feof(fin)){
			fscanf(fin,"%c",&c);
			s++;
		}
		
		if(!feof(fin)) k++;
		
	}
	
	fprintf(fout,"%d",s/k);
	
	return 0;
	
}