#include <string.h>
#include <stdio.h>
#include <algorithm>
using namespace std;

#define MAX 10000000

char  s[MAX];

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

  gets(s);
}

int main()
{
 int cuv=0,cr=0;

 _read();

 for(int i=0;i<strlen(s);i++)
  {
   if( strchr("!.? ,",s[i] )== NULL )
   {
    cuv++;

      while( strchr("!.? ,",s[i] )== NULL)
       {
         if(s[i]>='a' && s[i]<='z' || s[i]>='A' && s[i]<='Z')
           cr++;

       i++;
       }
   }


  }

 printf("%d",cr/cuv);

return 0;
}