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

int main(){
    short j=0, i;
    char cuv[1025], text[1025];
    unsigned long nrCuv=0, litere=0;
    FILE *fin = fopen("text.in", "r");
    FILE *fout = fopen("text.out", "w");
    fgets(text, 1024, fin);
    for(i=0; text[i]; i++)
	if(!isalpha(text[i])){
	    if(j){
		cuv[j] = 0;
		nrCuv++;
		litere+=strlen(cuv);
		j=0;
	    }
	}else
	    cuv[j++] = text[i];
    fprintf(fout, "%lu", litere/nrCuv);
    fcloseall();
    return 0;
}