I am learning about C linked lists from the All In One C Desk Reference For Dummies.
Whenever I run the code, I seem to be able to add new elements alright, but when I display the contents, only the data in the last node is shown.
I have checked and rechecked the code, but as far as I can tell, I am writing it the same as the book. Thanks for the help!
As I don't know which part is the part that is wrong, I have supplied the full example from the book, except for subbing out the fflush() functions for my own code. Exercise 6.2.1 (Book 6 - Chapter 2 - The Bank Program - bank.c (if that helps))
/* Includes */
#include<stdio.h>
#include<stdlib.h>
#include<string.h>
#include<ctype.h>
#include"../../myheaders/myinput.h"
/* Function Protoyypes */
void addNewAccount(void);
void listAll(void);
/* Structures and global variables */
struct account {
int number;
char lastname[15];
char firstname[15];
float balance;
struct account *next;
};
struct account *firsta, *currenta, *newa;
int anum = 0;
/* Main program */
int main()
{
char ch;
firsta = NULL;
do {
puts("\nA - Add a new account");
puts("L - List Accounts");
puts("Q - Quit this program\n");
printf("\tYour choice:");
ch = getonlychar(&ch);
ch = toupper(ch);
switch (ch) {
case 'A':
puts("Add new account\n");
addNewAccount();
break;
case 'L':
puts("Listing accounts");
listAll();
break;
case 'Q':
puts("Quit\n");
default:
break;
}
} while (ch!= 'Q');
return 0;
}
/* Definitions */
/* Add a new account */
void addNewAccount(void)
{
newa = (struct account *)malloc(sizeof(struct account));
/* Check to see if this is the first record.
* If so, then initialize all the pointers to this
* first structure in the database */
if (firsta == NULL) {
firsta = currenta = newa;
}
/* Otherwise, you must find the end of the structure list
* easily spotted by the NULL pointer) and add on the
* new structure you just allocated memorey for */
else {
currenta = firsta; /* Make first record current */
}
/* Loop through all records */
while (currenta->next != NULL) {
currenta = currenta->next;
/* The last reord is found */
currenta->next = newa; /* Save the address of new */
currenta = newa; /* Make current record new */
}
/* Now you just fill in the new structure */
anum++;
printf("%27s: %5i\n", "Account number", anum);
currenta->number = anum;
printf("%27s: ", "Enter customer's last name");
fgets(currenta->lastname, 14, stdin);
printf("%27s: ", "Enter customer's first name");
fgets(currenta->firstname, 14, stdin);
printf("%27s: ", "Enter account balance");
scanf(" %f", ¤ta->balance);
/* Finally, cap the new record with a NULL pointer
* so that you know it's the last record */
currenta->next = NULL;
}
void listAll(void)
{
if (firsta == NULL) {
printf("No records to show!\n");
}
else {
printf("%6s %-15s %-15s %11s\n", "Acct#", "Last", "First", "Balance");
currenta = firsta;
do {
printf("%6s %-15s %-15s %11s\n",
currenta->number,
currenta->lastname,
currenta->firstname,
currenta->balance);
} while ((currenta = currenta->next) != NULL);
}
}