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

struct tree {
    char value[50];
    struct tree* left;
    struct tree* right;
};


struct tree* read_tree(int* counter){
   
    //read one node
    int* c = counter;
    
    //printf("%d\n", *c);
    char buffer[50];
    memset(buffer,0,50);
    char* r = fgets(buffer,50,stdin);
    int x = strlen(buffer);
    buffer[x-1]='\0'; 
    
    if(r == NULL){
        printf("Chybna databaza\n");
        exit(0);
    }
    
     
    if(buffer[0] != '\0'){
        struct tree* node = calloc(1,sizeof(struct tree));
        memcpy(node->value, buffer,50);
        
        //count all nodes
        *c += 1;
        counter = c;
        
        //until i find "*", recursively read tree
        if(buffer[0] != '*'){ 
            
            //first check left side, if the isn't node, add it
            if(node->left == NULL){
                node->left = read_tree(counter);   
            }
            
            //than check right side
            if(node->right == NULL){    
                node->right = read_tree(counter);
            }
        }
        
        //if i found root with left and right node, decrease my counter
        if(node->left != NULL && node->right != NULL){
            *c -= 2;
            counter = c;
        }
         
        //if binary tree is okay, than counter is 1(there is one root)
        if(*c == 1){
              
              //if the user still inseting, than the databaze wrong
              r = fgets(buffer,50, stdin);  
              int x = strlen(buffer);
              buffer[x-1]='\0';
              if(buffer[0] != '\0'){
                  printf("Chybna databaza\n");
                  exit(0);    
              }
        }
       
        return node;
    }

}
void search(struct tree* this){
    
    //read answer
    char answer[5];
    memset(answer,0,5);
    char* r = fgets(answer,5,stdin);       

    if(r == NULL){
        printf("Koniec vstupu\n");
        exit(0);
    }
    
    if(answer[0] == '\n'){
        search(this);
    }
        
        if(answer[0] == 'a'){
           
           //if left node is answer, print it and end the program    
           if(this->left->value[0] == '*'){
                printf("%s\n", this->left->value);
                printf("Koniec\n");
                exit(0);
            }
            
            //else print it and continue searching 
            printf("%s\n", this->left->value);
            search(this->left);

        }
         
        else if(answer[0] == 'n'){ 
            
            //the same for the right side
            if(this->right->value[0] == '*'){
                printf("%s\n", this->right->value);
                printf("Koniec\n");
                exit(0);
            }
            printf("%s\n", this->right->value);
            search(this->right);

       }
   else{
       
       //if input is wrong
       printf("Nerozumiem\n");
       exit(0);
   } 
}

void destroy_tree(struct tree* root){
    
    //if root is NULL,than tree is empty
    if(root == NULL) return;
    
    //go to the left side and than to the right
    destroy_tree(root->left);
    destroy_tree(root->right);   
    free(root);
    root = NULL;
}
int count_leaves(struct tree* node){
    int count = 0;
     
    //if left and right nodes are empty
    if(node->left == NULL && node->right == NULL){
        count++;;
    } 
    else{
        
        //if left isn't NULL than count 
        if(node->left != NULL){
            count += count_leaves(node->left);
        }
        if(node->right != NULL){
            count += count_leaves(node->right);
        }   
    }
    return count;

}
int count_all(struct tree* node){
    if(node == NULL){
        return 0;
    }
    int count = 0;
    if(node->left != NULL){
        count += count_all(node->left);
    }
    if(node->right != NULL){
        count += count_all(node->right);
    }
    count++;
    return count;
}


int main(){

    printf("Expert z bufetu to vie.\n");

    struct tree* tree = NULL;
    int counter = 0;
    tree = read_tree(&counter);
    int count = count_leaves(tree);
     
    printf("Pozna %d druhov ovocia a zeleniny.\n", count);
    printf("Odpovedajte 'a' pre prvu moznost alebo 'n' pre druhu moznost.\n");
    
    printf("%s\n", tree->value);   
    search(tree);   
    destroy_tree(tree);
    
    return 0;
}