泄漏的內存，同時創造BST，解析需要援助

Question

Node *addToTree(Node *head, Node *newNode) { 
    if (head == NULL) { 
     head = newNode; 
    } else { 
     if (newNode->price < head->price) { 
      head->left = addToTree(head->left, newNode); 
     } else 
     if (newNode->price > head->price) { 
      head->right = addToTree(head->right, newNode); 
     } else 
     if (newNode->price == head->price) { 
      free(newNode); 
     } 
    } 
    return head; 
} 

Node *getCars(char *name) { 
    FILE *fp; 
    if ((fp = fopen(name, "r")) == NULL) { 
     return NULL; 
    } else { 
     Node *head = NULL; 
     Node *tmp; 
     char delim[2] = "|"; 
     char car[MAXLINELENGTH] = {0}; 
     char *token = NULL; 
     int ch; 
     while (!feof(fp)) { 
      tmp = malloc(sizeof(Node)); 
      tmp->left = tmp->right = NULL; 
      fgets(car, MAXLINELENGTH, fp); 
      token = strtok(car, delim); 
      while (token != NULL) { 
       if (strcmp(token, "model") == 0) { 
        token = strtok(NULL, delim); 
        strcpy(tmp->model, token); 
       } else 
       if (strcmp(token, "make") == 0) { 
        token = strtok(NULL, delim);  
        strcpy(tmp->make, token); 
       } else 
       if (strcmp(token, "price") == 0) { 
        token = strtok(NULL, delim);     
        tmp->price = atoi(token); 
       } else 
       if (strcmp(token, "year") == 0) { 
        token = strtok(NULL, delim);     
        tmp->year = atoi(token); 
       } else 
       if (strcmp(token, "color") == 0) { 
        token = strtok(NULL, delim);  
        strcpy(tmp->color, token); 
       } else 
       if (strcmp(token, "type") == 0) { 
        token = strtok(NULL, delim); 
        if (token == NULL) { 
         break; 
        } 
        strcpy(tmp->type, token); 
       } else 
       if (strcmp(token, "mileage") == 0) { 
        token = strtok(NULL, delim);  
        tmp->mileage = atoi(token); 
       } 
       token = strtok(NULL, delim); 
      } 
      if (check("makes.txt", tmp->make) != 1) { 
       continue; 
      } else 
      if (check("colors.txt", tmp->color) != 1) { 
       continue; 
      } else 
      if (check("types.txt", tmp->type) != 1) { 
       continue; 
      } else { 
       head = addToTree(head, tmp); 
      } 
     } 
     free(tmp); 
     fclose(fp); 
     return head; 
    } 
} 

所以對於一個家庭作業，我應該通過輸入文件與汽車10000左右的信息是，型號解析，顏色，型號，價格，行駛里程和年並根據它們的價格將它們輸入到BST中，當我運行代碼時，它說我在malloc的tmp指針處有274個字節丟失。我只是想知道這是什麼解決方案，而且我真的可以解析任何建議/幫助因爲我的getCars功能是醜陋的，它也需要大約15秒的時間運行，任何幫助，非常感謝！

Answer 1

有你的代碼中的多個問題：

• while (!feof(fp))永遠是錯的。閱讀：Why is 「while (!feof (file))」 always wrong?

• 您應該檢查所有屬性的缺失值。

• 當您無法匹配make，color或type時，您不會釋放節點。

• 解析循環後不應釋放tmp：它可能已被插入到BST中，如果文件爲空，它甚至可能未初始化。

• 令人驚訝的是，您不會將汽車插入BST而是另一輛汽車的價格相同......您應該更準確地檢查重複項。

這裏是一個改進版本：

Node *addToTree(Node *head, Node *newNode) { 
    if (head == NULL) { 
     head = newNode; 
    } else { 
     if (newNode->price < head->price) { 
      head->left = addToTree(head->left, newNode); 
     } else 
     if (newNode->price > head->price) { 
      head->right = addToTree(head->right, newNode); 
     } else 
     if (newNode->price == head->price) { 
      free(newNode); 
     } 
    } 
    return head; 
} 

Node *getCars(const char *name) { 
    FILE *fp; 
    if ((fp = fopen(name, "r")) == NULL) { 
     return NULL; 
    } else { 
     Node *head = NULL; 
     char delim[] = "|"; 
     char car[MAXLINELENGTH]; 

     while (fgets(car, sizeof car, fp)) { 
      Node *tmp = malloc(sizeof(Node)); 
      /* initialize all members */ 
      tmp->left = tmp->right = NULL; 
      tmp->model[0] = tmp->make[0] = tmp->color[0] = tmp->type[0] = '\0'; 
      tmp->price = tmp->year = tmp->mileage = 0; 
      char *token = token = strtok(car, delim); 
      while (token != NULL) { 
       if (strcmp(token, "model") == 0) { 
        token = strtok(NULL, delim); 
        if (token == NULL) break; 
        strcpy(tmp->model, token); 
       } else 
       if (strcmp(token, "make") == 0) { 
        token = strtok(NULL, delim);  
        if (token == NULL) break; 
        strcpy(tmp->make, token); 
       } else 
       if (strcmp(token, "price") == 0) { 
        token = strtok(NULL, delim);     
        if (token == NULL) break; 
        tmp->price = atoi(token); 
       } else 
       if (strcmp(token, "year") == 0) { 
        token = strtok(NULL, delim);     
        if (token == NULL) break; 
        tmp->year = atoi(token); 
       } else 
       if (strcmp(token, "color") == 0) { 
        token = strtok(NULL, delim);  
        if (token == NULL) break; 
        strcpy(tmp->color, token); 
       } else 
       if (strcmp(token, "type") == 0) { 
        token = strtok(NULL, delim); 
        if (token == NULL) break; 
        strcpy(tmp->type, token); 
       } else 
       if (strcmp(token, "mileage") == 0) { 
        token = strtok(NULL, delim);  
        if (token == NULL) break; 
        tmp->mileage = atoi(token); 
       } 
       token = strtok(NULL, delim); 
      } 
      if (check("makes.txt", tmp->make) != 1 
      || check("colors.txt", tmp->color) != 1 
      || check("types.txt", tmp->type) != 1) { 
       /* unrecognized make, type or color: discard entry */ 
       free(tmp); 
      } else { 
       head = addToTree(head, tmp); 
      } 
     } 
     fclose(fp); 
     return head; 
    } 
}