#include<cstdio>
FILE *f=fopen("text.in", "r");
FILE *g=fopen("text.out", "w");
char c,i;
int nrc,l,ok,s;
int main()
{
	while(!feof(f))
		{fscanf(f,"%c",&c);
		ok=0;
		for(i='a';i<='z'&&ok==0;i++) if(i==c) ok=1;
		for(i='A';i<='Z'&&ok==0;i++) if(i==c) ok=1;
		if(ok==1)
			{l++;
			if(s==0) {nrc++; s=1;}}
		else s=0;}
	fprintf(g,"%d", l/nrc);
	fprintf(g,"%c", '\n');
	fclose(f); fclose(g);
	return 0;
}