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#include <stdint.h>
#include <string.h>
#include <stdio.h>
#include <stdlib.h>
#include <stdbool.h>
#include <errno.h>
#include <ctype.h>

#include <algds/str.h>
#include <algds/vec.h>
#include <algds/hash_table.h>
#include <algds/mmhash.h>
#include <time.h>

#define PANIC do { \
    fprintf(stderr, "panic at %s:%d\n", __FILE__, __LINE__); \
    abort(); \
} while (0)

void expect_char(char e) {
    int c = fpeek(stdin);
    if (c != e) {
        PANIC;
    }
    fgetc(stdin);
}

typedef struct {
    char name[3];
} Tag;

void Tag_show(Tag self, FILE *fp) {
    printf("%c%c%c", self.name[0], self.name[1], self.name[2]);
}

VECTOR_DEF(Tag)
VECTOR_IMPL(Tag)

uint64_t Tag_hash(Tag self) {
    return mmhash(self.name, 3, 0);
}

bool Tag_eq(Tag a, Tag b) {    
    return a.name[0] == b.name[0]
        && a.name[1] == b.name[1]
        && a.name[2] == b.name[2];
}

HASH_TABLE_DEF(Tag, TagVector);
HASH_TABLE_IMPL(Tag, TagVector);

Tag parse_tag() {
    Tag t;
    t.name[0] = getchar();
    t.name[1] = getchar();
    t.name[2] = getchar();
    return t;
}

Tag Tag_new(const char *s) {
    Tag t;
    t.name[0] = s[0];
    t.name[1] = s[1];
    t.name[2] = s[2];
    return t;
}

Tag2TagVectorHashTable dag;

typedef struct {
    Tag t;
    int fft;
    int dac;
} CacheEntry;

uint64_t CacheEntry_hash(CacheEntry self) {
    uint64_t ret = Tag_hash(self.t);
    ret = mmhash(&self.dac, sizeof(int), ret);
    return mmhash(&self.fft, sizeof(int), ret);
}

bool CacheEntry_eq(CacheEntry a, CacheEntry b) {    
    return Tag_eq(a.t, b.t)
        && a.dac == b.dac
        && a.fft == b.fft;
}

HASH_TABLE_DEF(CacheEntry, Long);
HASH_TABLE_IMPL(CacheEntry, Long);

CacheEntry2LongHashTable cache;

long search(Tag src, int fft, int dac) {
    if (Tag_eq(src, Tag_new("out"))) {
        return fft * dac;
    }
    if (Tag_eq(src, Tag_new("fft"))) {
        fft = 1;
    }
    if (Tag_eq(src, Tag_new("dac"))) {
        dac = 1;
    }
    CacheEntry2LongHashTableIter cache_it =
        CacheEntry2LongHashTable_find(
            &cache,
            (CacheEntry){.t = src, .dac = dac, .fft = fft});
    if (cache_it != NULL) {
        return cache_it->val;
    }
    long res = 0;
    Tag2TagVectorHashTableIter dag_it = Tag2TagVectorHashTable_find(&dag, src);
    TagVector nexthops = dag_it->val;
    for (int i = 0; i < nexthops.size; i++) {
        res += search(nexthops.buffer[i], fft, dac);
    }
    CacheEntry2LongHashTable_insert(&cache, (CacheEntry){.t = src, .dac = dac, .fft = fft}, res);
    return res;
}

int main() {
    Tag2TagVectorHashTable_init(&dag);
    CacheEntry2LongHashTable_init(&cache);
    while (1) {
        int c = fpeek(stdin);
        if (isalpha(c)) {
            Tag t = parse_tag();
            expect_char(':');
            expect_char(' ');
            TagVector next;
            TagVector_init(&next);
            while (1) {
                int c = fpeek(stdin);
                if(!isalpha(c)) {
                    break;
                }
                TagVector_push_back(&next, parse_tag());
                c = fpeek(stdin);
                if (c == ' ') {
                    getchar();
                }
            }
            int c = fpeek(stdin);
            if (c == '\n') {
                getchar();
            }
            Tag2TagVectorHashTable_insert(&dag, t, next);
        } else {
            break;
        }
    }
    long ret = search(Tag_new("svr"), 0, 0);
    printf("%ld\n", ret);
    return 0;
}