Simple Lotto Game

I have developed a Lotto Game in C for my Assignment, it allows a user to enter one of the 6 menu options.

From the menu the user would be able to view the numbers they have chosen, another option would sort the numbers in ascending order, in this case I used bubble sort.

What it does in the 1st menu is read the 6 numbers that the user has entered from the keyboard. The number must range from 1-42 and if the user enters any number out of bounds it will give an error message. It also gives an error message if the user enters a number that they has entered already.

Another option will compare the users numbers with the winning numbers and see if they match.

It will also display how many times a number has been entered, for example if the user entered 5 twice from 4 games it will display Number 5 has been selected 2 times. without exiting the program. This can be selected from the menu too.

Last but not least, the last option from the menu exits the program.

I added key features such as displaying the menu after finishing with the current option from the menu and options 2,3,4 and 5 only to be selected if option 1 has been selected from the menu.

Please take a look and let me know how this code could be improved to make this a better Lotto Game.

Here is the code:

```
#include
#include
#define SIZE 6 // Size of the array as only 6 numbers are entered.
#define MAXOUT 43 // For Frequency use when displaying the numbers.
#define ZERO 0 // Replacing 0 with Zero.
#define ARRAYSIZE 500 // Storing the frequency, 500 should be enough.

/Prototypes/

//For Option 1
//
void menu_1(int, int);

//For Option 2
//
void menu_2(int*);

//For Option 3
//
void menu_3(int*);

//For Option 4
//
void menu_4(int, int);

//For Option 5
//
void menu_5(int, int);

//For Option 6
//
void menu_6();

//Ninja fix for entering the number twice.
//
int error_dubhandle(int *user_lottonumber);

//Out of bound error fix
//
void error_handle1();

//Main
//
int

Comments

Comments should tell the reader why you're doing something, not what you're doing. Comments like this are redundant:

//For Option 6
//
void menu_6();

Method Naming

Consider giving your functions more meaningful names that describe what they do. Using the example above, menu_6. Unless you already have the menu in your head the name is meaningless. A better name might be menu_exit_game.

Magic Numbers Vs Defines

Replacing magic numbers with meaningful constants is a good thing, however simply replacing a magic number with it's word value adds little value. Consider:

#define ZERO 0

What should ZERO be used for? You're using it as a direct replacement for 0 in your code, but not always:

int selectOnefirst = 0;

Another example is SIZE, SIZE of what? NUM_LOTTERY_NUMBERS perhaps? Naming is hard, however if you get it right it makes your programs a lot more expressive.

Unused variables

If you change your plan for your program, don't forget to clean up after yourself. For example in menu_5, you're declaring two variables that you're not using (j and adder).

Expressive names

Consider how much easier this would be to read with more expressive names and meaningful constants:

//If 6 numbers match the user wins this.
//
if(compareNum == 6)
{
    printf("Congratulations, You have won the Jackpot!");
}
//If 5 numbers and the bonus matches, the user wins this.
//
if(compareNum == 5 && bonusCount == 1)
{
    printf("Congratulations, You have won a Car!");
}

becomes:

if(matched_numbers == NUM_LOTTERY_NUMBERS)
{
    printf("Congratulations, You have won the Jackpot!");
}
if(matched_numbers == (NUM_LOTTERY_NUMBERS - 1) && matched_bonus)
{
    printf("Congratulations, You have won a Car!");
}

Be Consistent

Your using different conventions for naming your variables. You've got both selectOnefirst and user_lottonumber. Pick a naming strategy and be consistent throughout the program.

Bug when matching 3 numbers and 1 bonus

You're not returning from your matches and you're not using ifs, so if compareNum == 3, both of these if clauses are matched:

if(compareNum == 3 && bonusCount == 1)
{
    printf("Congratulations, You have won a Cinema Ticket!");
}

if(compareNum == ZERO || compareNum == 1 || compareNum == 2 || compareNum == 3)
{
    printf("Hard luck, you have not won anything.");
}

You could either update your code flow, or change the final if to something like:

if(compareNum <= 2 || (compareNum == 3 && !bonusCount))

StackExchange Code Review Q#134223, answer score: 10