创建唯一的随机数

本文介绍了创建唯一的随机数的处理方法，对大家解决问题具有一定的参考价值，需要的朋友们下面随着小编来一起学习吧！ 问题描述

我创建了以下方法以创建唯一的随机数。 （此唯一值属于树的节点）：

I have created the following method so as to create unique random numbers . (This unique values belong to the nodes of a tree):

static Random rand = new Random(); public static ArrayList<Node> go(int n) { ArrayList<Node> list = new ArrayList<Node>(); ArrayList<Integer> numList = new ArrayList<Integer>(); // TODO Auto-generated method stub for(int i = 1; i<=5; i++) { int number = rand.nextInt(10)+1; if(list.size()>0 && !check(list,number)) { i--; continue; } numList.add(number); Node node = new Node(); node.data = number; list.add(node); } int w = 0; for (Node d : list) { System.out.println(w+": "+d.data); w++; } return list; } private static boolean check(ArrayList<Node> list, int num) { // TODO Auto-generated method stub boolean b = false; /*if(list.size()==0) return true; */ for (Node node : list) { if(node.data == num) b = false; else b = true; } return b; }

但它不会创建唯一的数字，我的列表中仍然有重复数字。喜欢：

But it doesn’t create unique numbers and there are still duplicates in my list. Like :

0: 10 1: 1 2: 10 3: 5 4: 6

推荐答案

问题在于如果找到重复的数字，你不会在check函数内停止for循环。循环继续，b可以变回true。

The problem is that you don't stop the for loop inside the check function if it finds a duplicated number. The loop continues and b can change back to true.

你应该做的是例如：

private static boolean check(ArrayList<Node> list, int num) { for (Node node : list) { if(node.data == num) return false; } return true; }