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

char s[2000001];
int n;
int len=0;
int nr=0;

int main(void)
{
	freopen("text.in", "r", stdin);
	freopen("text.out", "w", stdout);


	while (scanf("%s", &s) != EOF)
	{
		n=strlen(s)-1;
		for(int i=0;i<=n;i++)
		{
			int j=i;
			while(isalpha(s[j])) j++, len++;
			if(j>i) nr++, i=j-1;
		}
	}

	printf("%d\n", len / nr);

	return 0;
}