7.1 数组去重的若干方法

function uniqArr (arr){
 var newArr = [];
  arr.sort(function (a,b){
      if(a - b){
        return -1
    }
    return 1
  })
  newArr.push(arr[0]);
  for(var i = 1; i < arr.length; i++){
      if(newArr[newArr.length - 1] === arr[i]) continue
    newArr.push(arr[i]);
  }
  return newArr;
}
function unique(arr){
  var newArr = [],
      item;
  for(var i = 0; i < arr.length; i++){
     item = arr[i];
        if(newArr.indexOf(item)===-1) newArr.push(item);
    }
  return newArr;
}