non repeating random, more efficiently.

non-rep-rand.js

  var pRandom = 1; 
  var total = 5; // top end of range
  var rand = Math.floor( Math.random()*total ); //get a rand

  while(rand == pRandom){ //are we the same, if so try again until we are not.
    rand = Math.floor( Math.random()*total ); //get a new random if we are the same
    console.log("try again"); 
  }

  pRandom = rand; //store the current random number to check against next time.
  console.log(rand); // output / do something with the #