#include <stdio.h>
#define nmax 10000010
using namespace std;
long long nrc,c;
char s[nmax];
int main() {
freopen("text.in","r",stdin);
freopen("text.out","w",stdout);
while (gets(s+1)>0) {
    for (int i=1;s[i];i++) {
        if ((s[i]>='a' && s[i]<='z') || (s[i]>='A' && s[i]<='Z')) c++; else
        if (i>1 && ((s[i-1]>='a' && s[i-1]<='z') || (s[i-1]>='A' && s[i-1]<='Z'))) nrc++;
    }
}
printf("%I64d",c/nrc);
return 0;
}