Prompt ֆունկցիա. JavaScript

function mean(arr) {
  let sum = 0;
  for (let i = 0; i < arr.length; i++) {
    sum += arr[i];
  }
  return sum/arr.length;
}
let arr = [25, 10, 5, 15, 20];
console.log(mean(arr));

// Console:
// 15

let len = +prompt("Input length")
let arr = [];
for (let i = 0; i < len; i++) {
  arr.push(+prompt("Input a number"));
}
console.log(arr);
function mean(arr) {
  let sum = 0;
  for (let i = 0; i < arr.length; i++) {
    sum += arr[i];
  }
  return sum/arr.length;
}
console.log(mean(arr));

// Console:
// [1, 2, 3, 4, 0]
// 2

function tetrNum(n) {
  let num = (n * (n + 1) * (n + 2))/6;
  return num;
}
console.log(tetrNum(5));

// Console:
// 35

// (C × 9/5) + 32 = F
function cel_far(c) {
  let f = c * 9/5 + 32;
  return f;
}
let c = +prompt("Input Celsius"); //1
console.log(cel_far(c));

// Console:
// 33,8

function rand(min, max) {
  return Math.floor(Math.random() * (max - min) ) + min;
}
function game(user) {
  let num = rand(5, 25);
  for (let i = 0; i < 10; i++) {
    if (isNaN(user)) {
      alert("It isn't a number");
      break;
    }
    else if (num < user) {
      alert("Too big");
      user = +prompt("Try again");
    }
    else if (num > user) {
      alert("Too small");
      user = +prompt("Try again");
    }
    else if (num == user) {
      alert("You win!");
      break;
    }
  }
}
let user = +prompt("from 5 to 25");
game(user);