#include<fstream>
using namespace std;
int main()
{char c;
long int i,okk,j,cuv,nrl,nrcuv,ok,m;

ifstream fin("text.in");
ofstream fout("text.out");
i=0;cuv=0;nrl=0;
fin.get(c);
okk=0;
do{ok=0;
   while(c>='a'&&c<='z' || c>='A'&&c<='Z'){nrl++;fin.get(c);ok=1;}
   fin.get(c);
   if(ok==1){i++;okk=1;  }
   m=(int)c;
   }while(fin.eof());


if(okk==1)fout<<nrl/i;
fin.close();
fout.close();
return 0;
}