Question

因此，该程序应该为汽车创建一个链表，其中包含年份信息，安全评级和模型。但是，当输出安全等级时，例如，如果用户输入“5”，程序会将其输出为某个非常大的数字，而不是用户输入的数字。

示例：如果用户输入

 Enter Year for Car: 1992

 Enter Rating for Car (0.00 - 100.00): 25.5

 Enter Model for Car: Chevy

节目输出是......

The Cars in the List Are As Follows: 
Year:1992 Rating:79960111893652368676401906121179136.00 Model:Chevy

什么时候应该......

The Cars in the List Are As Follows: 
Year:1992 Rating:25.50 Model:Chevy

我做错了什么？这是我的完整代码...

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

#define MAXSIZE 400

struct car {
    int year;
    float safeRating;
    char model[MAXSIZE];
    struct car *next;
};

typedef struct car Car;
typedef struct car *CarPtr;

void menu();
void printList(CarPtr);
CarPtr makeCar(int, float, char *);
CarPtr removeCar(CarPtr, int);
CarPtr addCar(CarPtr sPtr, int infoA, float infoB, char *infoC);
void viewCar(CarPtr sPtr, int infoA, float infoB, char *infoC);

int main()
{
    CarPtr startPtr;

    int infoA, choice;
    float infoB;
    char infoC;
    startPtr = NULL;

    menu();
    scanf("%d", &choice);    
    while (choice != 5){
      switch (choice){
        case 1: printf("\nEnter Year for Car: ");
                scanf("%d", &infoA);
                printf("\nEnter Rating for Car (0.00 - 100.00): ");
                scanf("%f", &infoB);
                printf("\nEnter Model for Car: ");
                scanf("%s", &infoC);
                startPtr = addCar(startPtr, infoA, infoB, &infoC);
                printList(startPtr);
                printf("\n");
                break;

        case 2: printf("\nEnter Car for deletion : ");
                scanf("%d", &infoA);
                startPtr = removeCar(startPtr, infoA);
                printList(startPtr);
                printf("\n");
                break;

        case 3: printf("\nEnter Car Number to View : ");
                scanf("%d", &infoA);
                viewCar(startPtr, infoA, infoB, &infoC);
                printf("\n");
                break;

        case 4: printList(startPtr);
                printf("\n");
                break;

        default: printf ("Invalid Option... Please Try Again \n");
                break;
      }
      menu();
      scanf("%d", &choice);    
    }

    return 0;
}

void menu()
{
  printf ("\t1: Insert Car into Ordered List\n");
  printf ("\t2: Remove Car from List\n");
  printf ("\t3: View Car from List\n");
  printf ("\t4: Printing the List\n");
  printf ("\t5: Exit\n");
  printf ("\tEnter Choice: "); 
}

CarPtr makeCar(int infoA, float infoB, char *infoC)
{
    CarPtr np = (CarPtr) malloc(sizeof(Car));
    np->year = infoA;
    np->safeRating = infoB;
    strcpy(np->model, infoC);
    np->next = NULL;
    return np;
}

void printList(CarPtr sPtr)
{
   if(sPtr == NULL){
      printf ("\nThere are no Cars to be Printed\n");
    }
    else {
      printf("The Cars in the List Are As Follows Sorted by Year: \n");
      while (sPtr != NULL) {
    printf("Year:%d Rating:%.2f Model:%s\n", sPtr->year, sPtr->safeRating, sPtr->model);
    sPtr = sPtr->next;
      }
    } 
}


CarPtr addCar(CarPtr sPtr, int infoA, float infoB, char *infoC)
{
        CarPtr newPtr, currPtr, prevPtr;

        newPtr = makeCar(infoA, infoB, infoC);

    prevPtr = NULL;
    currPtr = sPtr;

    while (currPtr != NULL && infoA > currPtr->year) {
        prevPtr = currPtr;
        currPtr = currPtr->next;
    }

    if (prevPtr == NULL) {  // inserting at the start of the list
        newPtr->next = sPtr;
        sPtr = newPtr;  // start of list has now changed
    } 
        else {
        newPtr->next = currPtr;
        prevPtr->next = newPtr;
    }
        return sPtr;
}


CarPtr removeCar(CarPtr sPtr, int infoA)
{
    CarPtr previousPtr, currentPtr, tempPtr;


    previousPtr = NULL;
    currentPtr = sPtr;

    if(sPtr == NULL){
      printf ("\nThe List is empty... No cars to be Removed\n");
      return sPtr;
    }

    while (currentPtr != NULL && currentPtr->year != infoA) {
    previousPtr = currentPtr;
    currentPtr = currentPtr->next;
    }
    if(currentPtr == NULL){
      printf("\nCar ( %d ) was not found \n", infoA);
    }
    else if (previousPtr == NULL){ // if node to be deleted is the first node
       tempPtr = sPtr;
       sPtr = sPtr->next;   // start of list has been changed
       printf("\nCar ( %d ) was deleted \n", tempPtr->year);
       free(tempPtr);
    }
    else{
       tempPtr = currentPtr;
       previousPtr->next = currentPtr->next;
       printf("\nCar ( %d ) was deleted \n", tempPtr->year);
       free(tempPtr);
    }

    return sPtr;

}

void viewCar(CarPtr sPtr, int infoA, float infoB, char *infoC)
{
    CarPtr previousPtr, currentPtr;


    previousPtr = NULL;
    currentPtr = sPtr;
    int position = 0;

    if(sPtr == NULL){
      printf ("\nThe List is empty... No cars to View\n");
      return;
    }

    while (currentPtr != NULL && currentPtr->year != infoA) {
    previousPtr = currentPtr;
    currentPtr = currentPtr->next;
        position++;
    }
    if(currentPtr == NULL){
      printf("\nCar ( %d ) was not found \n", infoA);
    }
    else{
       printf("\nCar ( %d ) Rating: %.2f Model: %s was found at position : %d\n", currentPtr->year, currentPtr->safeRating, currentPtr->model, (position + 1));
    }

}

Answer 1

您没有为汽车模型字符串分配任何空间。您是scanf("%s", &infoC);，但infoC是一个char，字符串没有空格。这会覆盖一些东西，可能会捣乱。然后，当你开车时，你会去strcpy，这将复制，直到它达到NULL字节。等等，等等。最好将其定义为char infoC[MAXSIZE]，以匹配struct car中的内容。

浮动链接列表未正确输出

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