function list(names){
  if(names.length == 0) return "";
  if(names.length == 1) return names[0].name;
  var arr = []
  // names.forEach(function(x){
  //   arr.push(x.name + ", ")
  // })
  for(let i = 0; i<names.length-2; i++){
    arr.push(names[i].name + ", ")
  }
  arr.push(names[names.length - 2].name)
  arr.push(names[names.length - 1].name)

  if(arr.length > 1){
    arr[arr.length - 1 ] = " & " + arr[arr.length - 1 ]
  }
  return arr.join("");
}

function bestList(names){
  return names.reduce(function(prev, current, index, array){
    if (index === 0){
      return current.name;
    }
    else if (index === array.length - 1){
      return prev + ' & ' + current.name;
    }
    else {
      return prev + ', ' + current.name;
    }
  }, '');
 }

list([{name: 'Bart'},{name: 'Lisa'},{name: 'Maggie'},{name: 'Homer'},{name: 'Marge'}])