#include<fstream>
#define L 40000000
using namespace std;

fstream f("text.in",ios::in),g("text.out",ios::out);

char s[L];
long long lun,lit,zero,cuv=0;

int main()
{
long long i;
while(!f.eof())f.getline(s,L);
f.close();
for(i=0;i<L;i++)
    {
    if(s[i]=='\0')break;
    }
lun=i;
for(i=0;i<lun;i++)
    {
    if( ( (int)(s[i])<97 || (int)(s[i])>122 ) && ( (int)(s[i])<65 || (int)(s[i])>90 ) ) s[i]='_';
    else lit++;
    }
for(i=0;i<lun;i++)
    {
    if(s[i]=='_')zero=0;
    else
        {
        if(!zero && ( ( (int)(s[i])>=97 || (int)(s[i])<=122 ) || ( (int)(s[i])>=65 || (int)(s[i])<=90 ) ))cuv++;
        zero=1;
        }
    }
g<<(long long)lit/cuv;
g.close();
return 0;
}