Menu system in c - c

Question

I'm having serious trouble with my program it is supposed to provide a menu and do all the functions the code is pretty explanatory my problem is I only have visual studios which doesnt allow scanf and scanf_s and messes with things so I use online compilers but those are still iffy. Can any one help and give me some tips. I'm having trouble with the math and function to list accounts, some whiles are empty as well I wasn't sure if that was best to use. I'm relatively new to this forum. It also can't have struct and can only be in C :-(
#include <stdio.h>
char name[20];
float avail_bal;
void options();
void open();
void list();
void deposit();
void withdraw();
void exit();
int main(void)
{
char option;
while(1){
printf("****Banking System WELCOME****\n");
printf("Enter 1-5 of the following options: \n");
option = getchar();
scanf("%c\n", &option);
switch(option)
{
case '1': open();
break;
case '2': list();
break;
case '3': deposit();
break;
case '4': withdraw();
break;
case '5': return 0;
default: exit();
break;
}
}
return 0;
}
void options()
{
printf("1. Open Account\n");
printf("2. List Accounts\n");
printf("3. Deposit\n");
printf("4. Withdraw\n");
printf("5. Exit");
}
void open()
{
float avail_bal = 0;
char name[20];
int acc_num;
printf("Open new account(enter number 1-5)\n\n");
scanf("%d", &acc_num);
printf("Account number: %d\n");
printf("Available balance: %f\n");
}
void list()
{
}
void deposit()
{
float add;
int acc_num;
printf("Which count do you want to deposit money in?");
scanf(" %d", &acc_num);
printf("Amount to deposit: ");
scanf("%f", &add);
while()
{
}
}
void withdraw()
{
int acc_num;
float withdraw;
printf("Account to withdraw from: ");
scanf("%d", &acc_num);
printf("Amount to withdraw from account: ")
scanf("%f", &withdraw);
while()
{
printf("Current balance for account %d: %f ");
break;
} acc_num++
}

Answer 1

The problem with scanf was interesting. Here is an example for how to do without (although you shouldn't) such that you can play with your code easier.
#include <stdio.h>
#include <stdlib.h>
// only 5 accounts possible
int accounts[5];
// each its balance
float avail_bal[5];
void options();
// open(P) is a standard Posix function
void bopen();
void list();
void deposit();
void withdraw();
// exit(3) is a standard C function
void pexit();
int main(void)
{
char option;
while (1) {
printf("****Banking System WELCOME****\n");
printf("Enter 1-5 of the following options: \n");
options();
option = getc(stdin);
// swallow the '\n'
getc(stdin);
switch (option) {
case '1':
bopen();
break;
case '2':
list();
break;
case '3':
deposit();
break;
case '4':
withdraw();
break;
case '5':
pexit();
default:
pexit();
}
}
return 0;
}
void options()
{
puts("1. Open Account");
puts("2. List Accounts");
puts("3. Deposit");
puts("4. Withdraw");
puts("5. Exit");
}
void bopen()
{
int acc_num;
char c;
puts("Open new account(enter number 1-5)");
c = getc(stdin);
getc(stdin);
// assuming ASCII here where the digits 0-9 start at place 48 in the table
acc_num = (int) c - 48;
if (acc_num < 1 || acc_num > 5) {
puts("Account number must be between one and five inclusive");
return;
}
if (accounts[acc_num] != 0) {
printf("Account number %d is already taken\n", acc_num);
return;
}
// mark account as taken
accounts[acc_num] = 1;
// spend a fiver for the new client for being a new client
avail_bal[acc_num] = 5.0;
printf("Account number: %d\n", acc_num);
printf("Available balance: %f\n", avail_bal[acc_num]);
}
void list()
{
int i;
for (i = 0; i < 5; i++) {
if (accounts[i] != 0) {
printf("Account 000%d: %f\n", i, avail_bal[i]);
}
}
}
void deposit()
{
float add;
int acc_num;
char c;
char s[100];
puts("Which account do you want to deposit money in?");
c = getc(stdin);
getc(stdin);
acc_num = (int) c - 48;
printf("Amount to deposit: ");
// to get a number without scanf() we have to read the input as a string
// (fgets() adds a '\0' at the end, so keep a seat free for it)
fgets(s, 99, stdin);
// and convert it to a double (atof() only for brevity, use strtod() instead)
add = atof(s);
avail_bal[acc_num] += add;
printf("Amount deposited %f\n", add);
}
void withdraw()
{
int acc_num;
float withdraw;
char c;
char s[100];
// all checks ommitted!
puts("Account to withdraw from: ");
c = getc(stdin);
getc(stdin);
acc_num = (int) c - 48;
puts("Amount to withdraw from account: ");
fgets(s, 99, stdin);
withdraw = atof(s);
avail_bal[acc_num] -= withdraw;
printf("Current balance for account %d: %f\n", acc_num, avail_bal[acc_num]);
}
void pexit()
{
// place logic to save data here or use a function triggered by atexit() for that task
puts("Imagine all of your data would have been put in a safe place!");
exit(EXIT_SUCCESS);
}
Just replace the constructs with scanf before you pass your work for grading.

Answer 2

If you're using integer values as options why you are using character's
#include <stdio.h>
char name[20];
float avail_bal;
void options();
void open();
void list();
void deposit();
void withdraw();
void exit();
int main(void)
{
int option;
printf("****Banking System WELCOME****\n");
void options();
printf("Enter 1-5 of the following options: \n");
scanf("%d",&option);
switch(option)
{
case 1: open();
break;
case 2: list();
break;
case 3: deposit();
break;
case 4: withdraw();
break;
case 5: return 0;
default: exit();
break;
}
return 0;
}
void options()
{
printf("1. Open Account\n");
printf("2. List Accounts\n");
printf("3. Deposit\n");
printf("4. Withdraw\n");
printf("5. Exit");
}
void open()
{
float avail_bal = 0;
char name[20];
int acc_num;
printf("Open new account(enter number 1-5)\n\n");
scanf("%d", &acc_num);
printf("Account number: %d\n");
printf("Available balance: %f\n");
}
void list()
{
}
void deposit()
{
float add;
int acc_num;
printf("Which count do you want to deposit money in?");
scanf(" %d", &acc_num);
printf("Amount to deposit: ");
scanf("%f", &add);
while()
{
}
}
void withdraw()
{
int acc_num;
float withdraw;
printf("Account to withdraw from: ");
scanf("%d", &acc_num);
printf("Amount to withdraw from account: ")
scanf("%f", &withdraw);
while()
{
printf("Current balance for account %d: %f ");
break;
} acc_num++
}