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

#define SIZE 256

struct tree {
    char value[SIZE];
    struct tree* left;
    struct tree* right;
};

void trim_whitespace(char* str) {
    int i = strlen(str) - 1;
    while (i >= 0 && isspace(str[i])) {
        str[i] = '\0';
        i--;
    }
}

struct tree* read_tree() {
    char buffer[SIZE];
    if (fgets(buffer, SIZE, stdin) == NULL) {
        return NULL;
    }
    if (buffer[0] == '\n') {
        return NULL;
    }
    trim_whitespace(buffer);
    struct tree* node = (struct tree*)calloc(1, sizeof(struct tree));
    strcpy(node->value, buffer);
    if (buffer[0] != '*') {
        node->left = read_tree();
        node->right = read_tree();
    }
    
    return node;
}

void destroy_tree(struct tree* tree) {
    if (tree == NULL) {
        return;
    }
    destroy_tree(tree->left);
    destroy_tree(tree->right);
    free(tree);
}

int count_answers(struct tree* tree) {
    if (tree == NULL) {
        return 0;
    }
    if (tree->value[0] == '*') {
        return 1;
    }
    return count_answers(tree->left) + count_answers(tree->right);
}

void run_knowledge_system(struct tree* node) {
    if (node == NULL) {
        return;
    }
    printf("%s\n", node->value);
    if (node->value[0] == '*') {
        return;
    }
    if (node->left != NULL || node->right != NULL) {
        char answer[10];
        if (fgets(answer, sizeof(answer), stdin) == NULL) {
            printf("Koniec vstupu\n");
	    exit(0);
            return;
        }
        if (answer[0] == 'a') {
            run_knowledge_system(node->left);
        } else if (answer[0] == 'n') {
            run_knowledge_system(node->right);
        } else {
            printf("Nerozumiem\n");
	    exit(0);
            return;
        }
    }
    return;
}

int main() {
    struct tree* knowledge_base = read_tree();
    char empty_line[SIZE];
    if (fgets(empty_line, SIZE, stdin) == NULL || empty_line[0] != '\n') {
        printf("Nespravna baza pravidiel.\n");
        if (knowledge_base != NULL) {
            destroy_tree(knowledge_base);
        }
        return 1;
    }
    if (knowledge_base == NULL) {
        printf("Nespravna baza pravidiel.\n");
        return 1;
    }
    int answer_count = count_answers(knowledge_base);
    printf("Expert z bufetu to vie.\n");
    printf("Pozna %d druhov ovocia a zeleniny.\n", answer_count);
    printf("Odpovedajte 'a' pre prvu moznost alebo 'n' pre druhu moznost.\n");
    run_knowledge_system(knowledge_base);
    printf("Koniec\n");
    destroy_tree(knowledge_base);
    return 0;
}