#include<stdio.h>
#include<string.h>
int main () {
	char n;
	int nr=0,nr2=0,end;
	FILE *in=fopen("text.in","r"), *out=fopen("text.out","w");
	end=fscanf(in,"%c",&n);
	while(end!=EOF){
		if((n>='A'&&n<='Z')||(n>='a'&&n<='z'))
			nr2++;
		if(n==' ')
			nr++;
		end=fscanf(in,"%c",&n);
	}
	nr+=2;
	fprintf(out,"%d\n",nr2/nr);
	return 0;
}