#include <stdio.h>
#include <string.h>

#define Nmax 4000000

char a[Nmax];
int n,nr,lung;

int main()
{
    int i=0;
    freopen("text.in","r",stdin);
    freopen("text.out","w",stdout);
    gets(a);
    n=strlen(a);
    while(i<n)
        {
            if((a[i]>='a' && a[i]<='z') || (a[i]>='A' && a[i]<='Z'))
                {
                    nr++;
                    int tmp=0;
                    while((a[i]>='a' && a[i]<='z') || (a[i]>='A' && a[i]<='Z') && i<n )
                        {
                            ++i;
                            ++tmp;    
                        }
                    lung+=tmp;
                }
            ++i;
        }
    printf("%d",lung/nr);
    return 0;   
}