Stuck in Infinite While Loop, what to do

Question

This does not accept any answer:

cout << "Restart yes or no: ";
cin >> retry;
while (retry != "yes" or retry != "no"){
    cout << "Restart yes or no: ";
    cin >> retry;
    system("cls");
}

If anybody can provide an alternative/fix it would be greatly appreciated.

Answer 1

Every string is different from either "yes" or "no". You meant to loop as long as the string is different from both "yes" and "no" - this means using the logical "and" operator, not the "or" operator:

while (retry != "yes" && retry != "no") {

Answer 2

Your code has retry != yes or retry != no. This condition is a tautology, and so will always evaluate to true.

Edit your code to:

cout << "Restart yes or no: ";
cin >> retry;
while (retry != "no"){
    cout << "Restart yes or no: ";
    cin >> retry;
    system("cls");
}

If you meant to loop until a yes or no is received, then the while loop should run until the string inputted is not equal to either. You meant to use a logical AND in place of the OR. The code should read:

while (retry != "yes" && retry != "no"){