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javascriptwhile-loopinfinite-loop

How do I stop an infinite loop from occurring while getting user input?

I'm a newbie writing a program that continues to ask the user for a number until the entered number is less than or equal to 100. I keep ending up in an infinite loop and I'm unsure of how to add the correct conditions to end the loop. 

let num;

while (!(num === 100 && num < 99)) {     // infinite loop
    num = Number(prompt("Enter a number: "));
    console.log(num);
}

I want to exit the loop when the user enters a number less than or equal to 100.

Solution

  • To resolve this issue use either 

    !(num === 100 || num < 100)  or
!(num <= 100)

    Issue: Num can never be both equal to 100 and less than 99 , so it will be false always and so while condition is true always

    let num; 
while (!(num <= 100)) { //or !(num === 100 || num < 100)
  num = Number(prompt("Enter a number: ")); 
  console.log(num); 
}