How to shuffle a list in javascript in O(n) time using the Fisher-Yates algorithm

gistfile1.js

/**
 * Returns number starting from offset up to n-1
 */
function getRandomWithOffset(n,offset) {
  return Math.floor(Math.random()*n+offset);
}
 
/**
 * Returns random integer from 0 to n-1
 */
function getRandom(n) {
    return getRandomWithOffset(n,0);
}
 
/** Fisher–Yates shuffle algorithm O(n) */
function shuffleList(list) {
    for (var i=list.length-1; i>0; i--) {
        var j = getRandom(i+1);
        var buffer = list[i];
        list[i]=list[j];
        list[j]=buffer;
    }
}