task ： Simulated bank ATM machine , Friendly interface is required
First, we analyze this problem ：
* simulation ATM machine , Realize the following functions ：1. Check the balance 2. deposit 3. withdraw money 0. sign out （ Lump sum deposit and withdrawal required ）
* Friendly interface is required .
system design ：
* Module differentiation , Determine the function and input of each module / output
* 1.showMenu modular
* function ： Display menu function , Read the user's operating system
* input ： nothing
* output ： Returns the function selection entered by the user
* 2.getMoney modular
* function ： Query the balance of user account .
* input ： nothing
* output ： Return the balance of user account
* 3.deposit（ storage ） modular
* function ： Increase the account balance according to the amount of money entered by the user
* input ： Amount to be deposited
* output ： nothing
* 4.withdraw modular
* function ： Reduce the balance according to the amount of money entered by the user , If the balance is not enough, you will be prompted that this operation cannot be completed .
* input ： Amount to be withdrawn .
* output ： nothing
Code display ：
Header file .h
#include<stdio.h> #include<stdlib.h> // Function declaration int showMenu(); double getMoney();
void deposit(double temp); void withdraw(double temp);
Block part ：.c
Technology