#include <iostream>
#include <fstream>
#include <string.h>
using namespace std;

char s[99999999];

ifstream in("text.in");
ofstream out("text.out");

void citire()
{
   in.get(s,99999999);
}

void count()
{
    long long int k=0,z=0;
    for(register long int i=0;i<strlen(s);i++)
         {
         if((int)s[i]>=65 and (int)s[i]<=90)
          {
              k++;
              if((int)s[i+1]<65 or (int)s[i+1]>90)
                         {
                           if((int)s[i+1]>90) {if((int)s[i+1]<97 or (int)s[i+1]>122 ) z++;}
                                    else z++;
                         }
          }
         if((int)s[i]>=97 and (int)s[i]<=122)
          {
              k++;
              if((int)s[i+1]<97 or (int)s[i+1]>122)
                            {
                               if((int)s[i+1]<97) {if((int)s[i+1]<65 or (int)s[i+1]>90 ) z++;}
                                          else z++;
                            }
          }
         }
      out<<k/z;
}

int main()
{
    citire();
    count();
}