#include <stdio.h>
#include <string.h>


int main()
{
	char s[50000];
	char *wtf;
	int n=0,c=0;
	
	FILE *in=fopen("text.in","r"),*out=fopen("text.out","w");
	fgets(s,999999,in);
	wtf = strtok (s," ,.-!?");
	while (wtf != NULL)
	{
		n+=strlen(wtf);
		c++;
		wtf = strtok (NULL, " ,.-!?");
	}
	n--; //removing \n
	c--; //removing \n
	fprintf(out,"%d\n",n/c);
	fclose(in);
	fclose(out);
	
	return 0;
}