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

char p[200003]; 
char *next;

inline char next_char()
{
	register char result = *next++;
	if (result == ' ')
		return *next++;
	else
		return result;
}

void expr( int& k, int& n )
{
	switch(next_char()) {
	case 'V':
		k = n = 1;
		return;
	case 'U':
		int k1, n1, k2, n2;
		expr( k1, n1 );
		expr( k2, n2 );
		k = (k1 > k2) ? k1 : k2;
		n = n1 + n2;
		return;
	case 'C':
		return expr( n, k );
	}
}

int main()
{
	while (gets(p)) {
		next = p; 
		int k, n;
		expr( k, n );
		printf( "%d\n", n );
	}
	return 0;
}