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

#define Nmax 8000000

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

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