請問大大以下是我的程式碼， import java.util.*; class quick { public static ArrayList sort(ArrayList all) { if(all.size() == 1) { return all; } String buf; ArrayList left = new ArrayList(); ArrayList right = new ArrayList(); for(int i=1;i Integer.parseInt(String.valueOf(all.get(i)))) { left.add(String.valueOf(all.get(i))); }else { right.add(String.valueOf(all.get(i))); } } if(left.size() == 0) { buf=String.valueOf(all.get(0)); all.clear(); all.add(buf); all.addAll(sort(right)); return all; }else if (right.size() == 0) { buf=String.valueOf(all.get(0)); all.clear(); all.addAll(sort(left)); all.add(buf); return all; } else { buf=String.valueOf(all.get(0)); all.clear(); all.addAll(sort(left)); all.add(buf); all.addAll(sort(right)); return all; } } public static void main(String[] args) { int arr[] ={3453,5349,4065,945,3660,6376,5348,1098,3344,1076,5293,6948,7410,7152,4985,4219,2229,9265,341,8015,8963,2441,8459,8823,1976,4605,1876,9150,3455,4020,5081,5910,1904,4307,5539,8228,3937,4406,9687,7686,5934,3356,2888,8195,4565,99,1186,5654,2910,6626,1815,3346,1974,8755,8925,7648,5762,2588,732,5,1759,6237,4390,5390,7656,5841,5307,4481,9468,2049,8300,6668,5810,8184,9050,3632,8032,4108,5627,8759,6142,458,1522,5909,6039,6343,3576,2178,4395,9896,476,3214,3764,5093,75,6357,1929,189,6698,6431}; ArrayList all=new ArrayList(); for(int i=0;i{ all.add(String.valueOf(arr[i])); } System.out.print(sort(all)); } } 如果我要算我排序的時間那我的時間點要怎麼設啊？？ 請大大跟我解迷一下！謝謝~

public static void main(String[] args) 
{ 
  //略
  long start = System.currentTimeMillis();
  System.out.println(sort(all)); 
  long end = System.currentTimeMillis();
  System.out.println(end - start); 
} 

單位是 milliseconds