I don't know what's wrong with this code

Question

Random rand = new Random();
int num1 = rand.Next(0, 9);
int num2 = rand.Next(0, 9);
int num3 = rand.Next(0, 9);
int num4 = rand.Next(0, 9);

While(((num1 != num2) && (num1 != num3) && (num1 != num4) && (num2 != num3) && (num2 != num4) && (num3 != num4)) == false)
{
while(num1 == num2)
{
num2 = rand.Next(0, 9);
}

while(num1 == num3)
{
num3 = rand.Next(0, 9);
}

while(num2 == num3)
{
num3 = rand.Next(0, 9);
}

while(num1 == num4)
{
num4 = rand.Next(0, 9);
}

while(num2 == num4)
{
num4 = rand.Next(0, 9);
}
}

Answer 1

check line 7

While ❎
while ✅

and why are you doing Inefficient duplicate checking? your inner loops tried to fix one duplicate at a time, but changing num2 to avoid num1 could make it equal to num3 and blabla... and also it have risk of infinite loop.

Answer 2

here's another method:

https://sololearn.com/compiler-playground/cwzYaNCMIOsb/?ref=app

Answer 3

Thank you so much!
I don't know about C# well so that's the reason (I'm not a expert.).

Answer 4

Thank you