text: /**
   * Created by chao on 15/10/1.
   */
  
  // add member to arr
  
  // push() unshift()
  // push() to the arr end
  
  var nums = [1,2,4,5]
  console.log(nums)
  nums.push(6)
  console.log(nums)
  nums[nums.length]=nums.length
  console.log(nums)
  //unshift()
  
  //add new member at the arr start by loop
  
  var nums_1 = [2,3,5]
  var newnum = 1;
  var N = nums_1.length;
  for(var i =N; i>=0;--i){
      nums_1[i] = nums_1[i-1]
  }
  nums_1[0]=newnum;
  console.log(nums_1)
  
  
  var nums_2 = [2,3,4,5];
  console.log(nums_2);
  var newnum_1 = 1;
  nums_2.unshift(newnum_1);
  console.log(nums_2);
  nums_3 = [3,4,5];
  nums_3.unshift(newnum_1,1,2)
  console.log(nums_3)
  
  
  
  