#include<stdio.h>
#include<string.h>
#include<ctype.h>
int  main()
{
char s[60000];
FILE* f=fopen("text.in","r");
FILE *g=fopen("text.out","w");
long nrl=0;
long nr=0,i;
while(!feof(f))
 {
  fscanf(f,"%s",s);
  if(s[0]!='-')
	  {for(i=0;i<strlen(s);i++)
		if(isalpha(s[i]))
		   nrl++;
	  nr++;
	  if(strchr(s,'-'))

		   nr++;
	  }
  }

fprintf(g,"%ld",nrl/nr);
fclose(g);
fclose(f);
return 0;
}