/*
#include<iostream>
#include<fstream>
#include<algorithm>

int v[50]={0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,18,19,20,21,22,23,24,25,26,27,28,29,30};
using namespace std;
int main(void)
{
	int i,n,k;
	fstream f,g;
	f.open("combinari.in",ios::in);
	g.open("combinari.out",ios::out);
	f>>n>>k;
	do
	{
		for (i=1;i<=k;i++)
			g<<v[i]<<" ";
		g<<"\n";
		}while (next_permutation(v+1,v+n+1));
		
}
*/
/*
#include<iostream>
#include<fstream>
#include<string.h>
using namespace std;
char cuv[10000000];
int main(void)
{
	unsigned long long int i,n,k,c=0,lung=0;
	fstream f,g;
	f.open("text.in",ios::in);
	g.open("text.out",ios::out);
	while (f>>cuv)
	{
		c++;
		lung+=strlen(cuv);
	}
	g<<lung/c;
		
}
*/

#include<iostream>
#include<fstream>
using namespace std;
long long nrl,nrcuv;
int main(void)
{
	char ch,chp='9';
	
	fstream f("text.in",ios::in), g("text.out",ios::out);
	while (f>>noskipws>>ch)
	{
		if ((int(ch)>=65 && int(ch)<=90)||(int(ch)>=97 && int(ch)<=122))
		{
			
				nrl++;
		}
		else
		{
			if((int(chp)>=65 && int(chp)<=90)||(int(chp)>=97 && int(chp)<=122))
				nrcuv++;
		}
		chp=ch;
	}
	f.clear();
	f.seekg(-1,ios::end);
	f>>ch;
		if ((int(ch)>=65 && int(ch)<=90)||(int(ch)>=97 && int(ch)<=122))
		{
			
				nrcuv++;
		}
	g<<nrl/nrcuv;
}