Function to check for negatives

[jlpurnell]

I have a main program that asks for several inputs, days, rate, expenses, and purchases.

Can I have a function that checks all of these to make sure that they are greater than 0 and then goes back to the variable that is less than zero and then the user can input a correct value?

I have done this before:

while (deposit < 0.0)
{
cout << "The deposit cannot be negative.\n";
cin >> deposit;
}

But, I would have to write this several times after each variable.

I am very beginner, so I'm thinking I would want a function to run each time to check for an invalid entry, but I don't know how I would create a generic function to test all variables and then go back to the appropriate spot to continue.

[willynilly]

A do-while loop would
help you.

[metulburr]

It would be done with simple control flows. If it is negative continue the loop and re-ask, otherwise go on and do something with the data, or ask for the next value in the sequence:

int main(){
    double value;
    while (true){
        std::cout << "Enter positive value: ";
        std::cin >> value;
        if (value < 0){
            std::cout << "I said positive!" << std::endl;
            continue;
        }
        std::cout << "doing something with the value of " << value << std::endl;
            
    }
    
}

[jlpurnell]

Thanks!