#include <fstream>
using namespace std;
ifstream f("text.in");
ofstream c("text.out");
int nr1,s;
char ch,ch1;
int main()
{
    ch1=f.get();
    while(!f.eof())
    {
        ch=f.get();
        if(!f.eof()){
        if(ch>='a' && ch<='z' || ch>='A' && ch<='Z' || ch>='0' && ch<='9')
             s++;
             else
             if(ch1>='a' && ch1<='z' || ch1>='A' && ch1<='Z' || ch1>='0' && ch1<='9')
             nr1++;
       ch1=ch;
        }
    }
    if(ch>='a' && ch<='z' || ch>='A' && ch<='Z' || ch>='0' && ch<='9')
       nr1++;
    c<<s/nr1;
    return 0;
}