Randomize number on click but never the same number

You could use a recursive function to generate a unique number.

I am implementing the function with an array which will hold the value of the previously used numbers and the Math.random() to generate the random number.

steps:

Step 1. Create a function.
Step 2: Generate a random number
step 3: check if it exists in the array
step 4: if already exists then call the function again otherwise we have the unique random number.

if the function exceeds the max random numbers then it will return a negative number. You could handle this according to your need, you could reset the array or something like that.

Try this.

$('button').click(function(){
  var nomeri = genRandomNum();
  console.log(nomeri);
});

let random = [];
function genRandomNum() {
  let randNum = Math.floor(Math.random() * 100);
  if (random.length >= 100) {
    return -1;
  } else if (random.includes(randNum)) {
    return genRandomNum();
  } else {
    random.push(randNum);
    return randNum;
  }
}

<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>
<button>Random Number</button>

Here is a more efficient way to do this. Doing it the way Sohail proposed could result in many many function calls, especially once there have been a large share of the available numbers added to the array. Each time it finds a number that has been used before it calls the function again in search of a random number that has not been used yet. It could take a long time to find an unused number.

This way you are guaranteed to get an unused number the first time you call the function.

1) All possible answers are added to an array. 2) Then a random value from that array is returned. 3) The array is then modified to exclude the values already returned.

See: array.splice()

const allPossibleValues = [];
for(let i = 0; i < 100; i++){
  allPossibleValues.push(i);
}
 
 $('button').click(function(){
    if(allPossibleValues.length){
      let nomeri = returnRandomValueFromArray();
      console.log(nomeri);
    }
    else {
      console.log("No more values left");
    }
});

function returnRandomValueFromArray() {
  const randomIndex = Math.floor(Math.random() * allPossibleValues.length);
  const randomValue = allPossibleValues[randomIndex];
  allPossibleValues.splice(randomIndex, 1);
  return randomValue;
}

<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>
<button>დამაკლიკე</button>