#include <stdio.h>

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

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

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

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

	return 0;
}