How do I stop a program if the user gets something wrong?

Question

I am writing a program where the user enters how much money he has and if it's under 50 it would say"

Sorry not Enough

and I want the program to end there.

Here is the code I have written:

cin >> money;
if (money <= 50) {
    cout << "Sorry not enough" << endl;
}
cout << "Here are the items you can buy" << endl;
int a = 50;
int b = 200;

of course this is not the entire code I wrote. If the person wrote a number less than 50, how do I make the code stop?

Thanks!

Do you mean *exit* the program? *Return* from the `main` function? — Some programmer dude, Jul 11 '16 at 05:37
Do you want a full stop? Then just write `exit(0);` in the `if` block. — πάντα ῥεῖ, Jul 11 '16 at 05:38

score 1 · Answer 1 · edited Jul 11 '16 at 06:35

1

You have to write return after:

cout << "Sorry not enough" << endl;

This will stop the code.

edited Jul 11 '16 at 06:35

ani627

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answered Jul 11 '16 at 05:37

Szymon

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Do I have to write "return 0;"? – Miguel Nunez Jul 11 '16 at 05:41
Yes, as explained here: http://stackoverflow.com/questions/19402295/any-difference-between-return-vs-return-0-in-c – Szymon Jul 11 '16 at 05:47

Jesper Juhl · Answer 2 · 2016-07-11T05:44:25.707

1

Your program ends when you return from main(), so you should arrange for that to happen.

Alternatively you could call exit(), but that's a bad idea since destructors won't run.

edited Jul 11 '16 at 05:44

answered Jul 11 '16 at 05:39

Jesper Juhl

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ani627 · Answer 3 · 2016-07-11T05:44:21.280

1

You can write your code like this:

cin >> money;
if (money <= 50) {
    cout << "Sorry not enough" << endl;
}
else {
   cout << "Here are the items you can buy" << endl;
   // Operations you want to perform 
}

edited Jul 11 '16 at 05:44

answered Jul 11 '16 at 05:39

ani627

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@MiguelNunez: Glad I could help! – ani627 Jul 11 '16 at 05:45

Vaibhav Bajaj · Answer 4 · 2016-07-11T05:47:50.843

1

Using a return statement or the exit() function in C++ will exit the program. Your code would look like:

int main()
{
cin >> money;
if (money <= 50) {
    cout << "Sorry not enough" << endl;
    return 0;
}
cout << "Here are the items you can buy" << endl;
int a = 50;
int b = 200;
}

Conversely, with exit() function, it would look like:

#include<stdlib.h> //For exit function
int main()
{
cin >> money;
if (money <= 50) {
    cout << "Sorry not enough" << endl;
    exit(0);
}
cout << "Here are the items you can buy" << endl;
int a = 50;
int b = 200;
}

edited Jul 11 '16 at 05:47

answered Jul 11 '16 at 05:42

Vaibhav Bajaj

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`return EXIT_FAILURE;`, maybe. – R Sahu Jul 11 '16 at 05:46
or `return EXIT_SUCCESS;`. – R Sahu Jul 11 '16 at 05:47
I changed it to `return 0;`. Does that indicate success? – Vaibhav Bajaj Jul 11 '16 at 05:48
Whether the program returns with success or failure depends on whether the exit status is used to control something in the executing environment. – R Sahu Jul 11 '16 at 05:49
Yes, `return 0;` is the same as `return EXIT_SUCCESS;`. – R Sahu Jul 11 '16 at 05:50

How do I stop a program if the user gets something wrong?

4 Answers4