text: //importance 5//
  //a = 2, b = 2, c =2, d = 1//
  
  //importance 3//
  //a = 4, x = 5//
  
  //importance 5//
  //10; -1; 1; 2; 6; 9px; $45; 2; NaN; infinity; "-9 5"; -14; 1; NaN; - 2
  
  //importance 5//
  let a = prompt("First number", 1);
  let b = prompt("Second number", 2);
  
  alert(+a + +b);//3