#include<stdio.h>
#include<ctype.h>
int main()
{char c, d;
int cuv=0, lit=0, v=0, ok;
FILE*f=fopen("text.in", "r");
FILE*g=fopen("text.out", "w");
fscanf(f,"%c",&c);
while (!feof(f)) {ok=0;
				if (isupper(c)) ok=1;
				if (islower(c)) ok=1;
				if (ok==1) v++;
				else if (v>0) {lit=lit+v; v=0; cuv++;}
				d=c;
				fscanf(f,"%c",&c);
				}
ok=0;
if (isupper(d)) ok=1;
if (islower(d)) ok=1;
if (ok==1) {lit=lit+v; cuv++;}
fprintf (g, "%d", lit/cuv);
fclose(f);
fclose(g);
return 0;
}