#include <stdio.h>
#include <stdlib.h>

#define MB 1048576

int main() 
{       
	FILE *f, *g;
	int cuvnr = 0, cuvsize = 0, totalcuvsize = 0;
	char s;
	f = fopen("text.in" , "rt");
	g = fopen("text.out" , "wt");
	do {	
		fscanf(f, "%c", &s);
		if (((s >= 'A') && (s <= 'Z')) || ((s >= 'a') && (s <=
				'z'))) {
			if (cuvsize == 0) {
				cuvsize++;
				cuvnr++;
			}
			else
				cuvsize++;
		}
		else {
			totalcuvsize += cuvsize;
			cuvsize = 0;
		}

	} while (s != EOF);
	fprintf(g, "%d", totalcuvsize/cuvnr);
	return 0;
}