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

#define ex(c) strchr("abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ",c)

int main()
{
    FILE *in=fopen("text.in","r");
    int n=0, l=0;
    char c,cc='@';
    while ((c=fgetc(in))!=EOF)
    {
        if (ex(c)!=NULL)
            l++;
        if (!ex(c) && ex(cc))
            n++;
        cc=c;
    }
    if (ex(cc))
        n++;
    fclose(in);
    FILE *out=fopen("text.out","w");
    if (!n)
        fprintf(out,"%d",0);
    else
        fprintf(out,"%d",l/n);
    fclose(out);
    return 0;
}