I'm trying to get a number of rooms and it can't be less than 1. I have this do loop with and if statement but when i enter invalid input it just outputs invalid output and goes onto my next function.
Code:int num_of_rooms() { int num_rm, valid = 1; do { cout << "Enter the number of rooms: "; cin >> num_rm; if (num_rm < 1) { valid = 0; cout << "Invalid input\n"; } }while(valid = 0); return num_rm; }
Might be that 'while (valid = 0)' should have 2 ='s ('while (valid == 0)'). Also just so you know, if the first time you input less than one, it will never break from the loop because 'valid' will never change.
Also, since you're using valid like a boolean, you may as well make it a bool.
It is too clear and so it is hard to see.
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> while(valid = 0)
This makes it false, even if it's still true!
Compare, don't assign.
Making it a bool variable would help, then you can just say
while ( !valid )
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Even if it's not bool, the expression (!valid) evaluates correctly for checking if the value is zero (or NULL for that matter). Otherwise backwards compatibility with C would be broken.Originally Posted by Salem
I agree that the variable should be bool, since the "valid" variable only holds two possible values: true or false. This helps indicating the correct use of the variable. [It makes sure no-one thinks it's "the number of valid entries" or some such].
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Mats
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