Member Avatar for FraidaL

Is it possible to loop an if-else statement? How would such a thing be coded. Basically, this code allows the user to enter a value for a month. If it's not from 0-12 it asks the user to enter a new value. How could I get that to go through the if-else again to see if it's a valid number? Also, if I wanted to say if it's less than 0 it's invalid does that need to be it's own if statement or I could I somehow combine that with something else?

#include <iostream>

using namespace std;

int main ()
{
    cout << "Please enter a numerical value of a month: ";
	int month;
	
	cin >> month;
	
	if (month<=12)
	{
		cout << "A valid month has been entered.";
	}
	
	else
	{
		cout << "That is not a valid entry. Please enter a new value. ";
		int month;
		cin >> month;
	}
	
    return 0;
}
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  • Latest Post Latest Post by Tygawr

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Generated

Validation belongs inside a loop so the same if/else runs until a good month is provided. ’s outline (loop → ask → validate → repeat) and ’s remark about using the loop condition are correct. The original code has two practical problems: a second month declaration inside the else creates a short‑lived variable and leaves the outer value unchanged, and there’s no repetition that revalidates the newly entered value. ’s classification of valid vs invalid inputs is on the right track but needs surrounding repetition to be effective.

A simple, robust pattern keeps an if/else for the check but performs it inside a loop that only exits on valid input. Use one combined condition for the numeric range (calendar months are normally 1–12 unless 0 is intentionally allowed) and handle non‑numeric input by clearing and discarding the bad token before the next read.

#include <iostream>
#include <limits>

int main() {
    int month = 0;
    while (true) {
        std::cout << "Enter month (1-12): ";
        if (!(std::cin >> month)) {                 // non-integer entered
            std::cout << "Please enter an integer.\n";
            std::cin.clear();
            std::cin.ignore(std::numeric_limits<std::streamsize>::max(), '\n');
            continue;
        }
        if (month >= 1 && month <= 12) {           // valid range
            std::cout << "A valid month has been entered.\n";
            break;
        } else {                                    // invalid range
            std::cout << "Invalid month; try again.\n";
        }
    }
    return 0;
}

Notes and common pitfalls: do not redeclare the input variable inside the else (that shadows the outer variable). If 0 is intended as a sentinel, adjust the valid range accordingly. A do { ... } while (month < 1 || month > 12); is a shorter alternative, but the shown while(true) plus if/else keeps the required if/else structure while ensuring repeated validation.

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Member Avatar for Ancient Dragon

You may need to rearrange your program a bit, removing the if-then-else statemet.

beginning of loop
    ask for user input
    if input is valid then exit the loop
    display error message
end of loop
display message that input is valid
Edited by Ancient Dragon because: n/a
Member Avatar for FraidaL

How do I exit a loop? The program has to be an if-else statement.

Member Avatar for WaltP

By using the proper comparison in the loop statement itself, like
while (this is true)

Member Avatar for Ancient Dragon

>>display message that input is valid

Well, then just change my previous post a little

beginning of loop
    ask for user input
    if input is valid then 
       display message that input is valid
       exit the loop
    else
        display error message
end of loop
Member Avatar for Tygawr 
void IfElseLoopExample()
{
	int Month;
	cout << "Please enter a numerical value of a month: " << endl;
	cin >> Month;
	
	if(Month <= 12)
	{
		cout << "A valid month has been entered." << endl;
	}
	else if(Month > 12 || Month < 0)
	{
		cout << "That is not a valid entry. Please enter a new value." << endl;
		cin >> Month;
	}
}
commented: Doesn't answer the question -4
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