#include <limits.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
static struct {
	char a, b, c;
} pairs[128];
static size_t len;
static char *step(const char *prev) {
	char *next = malloc(1 + strlen(prev)*2);
	char *ptr = next;
	size_t i;
	for (i = 0; prev[i+1]; ++i) {
		*ptr++ = prev[i];
		for (size_t j = 0; j < len; ++j) {
			if (prev[i] != pairs[j].a || prev[i+1] != pairs[j].b) continue;
			*ptr++ = pairs[j].c;
			break;
		}
	}
	*ptr++ = prev[i];
	*ptr = '\0';
	return next;
}
int main(void) {
	size_t cap = 0;
	char *polymer = NULL;
	ssize_t n = getline(&polymer, &cap, stdin);
	if (polymer[n-1] == '\n') polymer[n-1] = '\0';
	while (EOF != scanf(" %c%c -> %c\n", &pairs[len].a, &pairs[len].b, &pairs[len].c)) {
		len++;
	}
	for (int i = 0; i < 10; ++i) {
		char *next = step(polymer);
		free(polymer);
		polymer = next;
	}
	int freq[128] = {0};
	for (size_t i = 0; polymer[i]; ++i) {
		freq[polymer[i]]++;
	}
	int min = INT_MAX, max = INT_MIN;
	for (int i = 'A'; i <= 'Z'; ++i) {
		if (freq[i] && freq[i] < min) min = freq[i];
		if (freq[i] > max) max = freq[i];
	}
	printf("%d\n", max - min);
}