#include <cstdio>
#include<cstring>
using namespace std;
int s,nr,t,nrl;
char x,x1;
int main()
{
    freopen("text.in","r",stdin);
    freopen("text.out","w",stdout);
    while(1)
    {
        t=scanf("%c",&x);
        if(t<0) break;
        if(x>='A'&&x<='Z')nrl++;
        else if(x>='a'&&x<='z')nrl++;
        else if(x1>='a'&&x1<='z'){s=s+nrl;nrl=0;nr++;}
        else if(x1>='A'&&x1<='Z'){s=s+nrl;nrl=0;nr++;}
        x1=x;
    }
    printf("%d",s/nr);
    return 0;
}