#include <cstdio>
#include <cstring>
using namespace std;

char q[300000];

int main()
{


    freopen("text.in","r",stdin);
    freopen("text.out","w",stdout);

    int n, i, s, t, d, k;
    s = d = 0;

    while( scanf("%s",q) != EOF ){
        n = strlen(q);
        for( i = 0; i < n; ){
            if( ( q[i]>='a' && q[i]<='z') || (q[i]>='A' && q[i]<='Z')){
                for( i = i; ( q[i]>='a' && q[i]<='z') || (q[i]>='A' && q[i]<='Z' ); ++i ) s++;
                d++;
            }
            else i++;
        }
    }

    //printf("%d %d\n",s,d);
    printf("%d",s/d);

    return 0;
}