#include <stdio.h>

int main(){
	char c1,c2,c3,c4,c5;
	int b=0;

	scanf("%c%c%c%c%c", &c1, &c2, &c3, &c4, &c5);

	if(c1>='a' && c1<='z')
		b++;
	if(c2>='a' && c2<='z')
		b++;
	if(c3>='a' && c3<='z') 
                b++;
	if(c4>='a' && c4<='z') 
                b++;
	if(c5>='a' && c5<='z') 
                b++;

	printf("%d\n",b);

	return 0;
}