private void simpleRandom(int start, int end, int count) { 
    System.out.println("朴素随机算法："); 
    StringBuffer buffer = new StringBuffer(); 
    for (int i = 0; i < count; i++) { 
      int random = NumberUtils.randomInteger(start, end); 
      buffer.append(i == 0 ? ("[" + random) : (", " + random)); 
    } 
    buffer.append("]"); 
    System.out.println(buffer); 
  } 

private void checkRandom(int start, int end, int count) { 
    System.out.println("检查存在性随机算法："); 
    StringBuffer buffer = new StringBuffer(); 
    List<Integer> save = new ArrayList<>(); 
    for (int i = 0; i < count; i++) { 
      int random = NumberUtils.randomInteger(start, end); 
      if (exits(save, random)) { 
        i--; 
        continue; 
      } 
       
      save.add(random); 
      buffer.append(i == 0 ? ("[" + random) : (", " + random)); 
    } 
    buffer.append("]"); 
    System.out.println(buffer); 
  } 

 private void removeRandom(int start, int end, int count) { 
    System.out.println("元素移除随机算法："); 
    StringBuffer buffer = new StringBuffer(); 
    List<Integer> numbers = initList(start, end); 
    for (int i = 0; i < count; i++) { 
      int random = NumberUtils.randomInteger(count - i); 
      buffer.append(i == 0 ? ("[" + numbers.get(random)) : (", " + numbers.get(random))); 
      numbers.remove(random); 
    } 
     
    buffer.append("]"); 
    System.out.println(buffer); 
  } 

 private void statusRandom(int start, int end, int count) { 
    System.out.println("状态转移随机算法："); 
    StringBuffer buffer = new StringBuffer(); 
    int[] status = new int[end + 1]; 
    for (int i = 0; i < count; i++) { 
      int random = NumberUtils.randomInteger(start, end); 
      System.err.println(random); 
      if (status[random] == 0) { 
        buffer.append(i == 0 ? ("[" + random) : (", " + random)); 
        status[random] = random == end ? start : (random + 1); // 不可能有在start之前的数字 
      } else { 
        // 状态转移 
        int index = random; 
        do { 
          index = status[index]; 
        } while (status[index] != 0); 
         
        buffer.append(i == 0 ? ("[" + index) : (", " + index)); 
        status[index] = index == end ? start : (index + 1); // 不可能有在start之前的数字 
      } 
    } 
     
    buffer.append("]"); 
    System.out.println(buffer); 
  } 

private List<Integer> simpleFloyd(List<Integer> list, int count, int start, int end) { 
    if (count == 0) { 
      return list; 
    } 
    list = simpleFloyd(list, count - 1, start, end - 1); 
    int random = NumberUtils.randomInteger(start, end); 
    if (list.contains(random)) { 
      list.add(end); 
    } else { 
      list.add(random); 
    } 
    return list; 
  } 

private List<Integer> iterationFloyd(int start, int end, int count) { 
    System.out.println("迭代Floyd随机算法："); 
    List<Integer> list = new ArrayList<>(); 
    for (int i = end - count + 1; i < end; i++) { 
      int random = NumberUtils.randomInteger(start, i); 
      if (list.contains(random)) { 
        list.add(i); 
      } else { 
        list.add(random); 
      } 
    } 
     
    return list; 
  }