java List.add操作可以指定位置,addAll也可以指定: 使用: public class Test02 { public static void main(String[] args) { ArrayList<String> list = new ArrayList<>(); list.add("str1"); list.add("str2"); list.add(1,"str222"); for (int
写了个Java的查找二叉树,用递归做的,不用递归的还没弄出来.先贴一下.回头再研究. BTreeTest.java: public class BTreeTest{ class Node{ Node left, right; int data; Node(int newData){ left = null; right = null; data = newData; } } Node root = null; int count = 0; boolean canFind = false; pub
在数组中查找一个元素,Arrays提供了一个方便查询的方法.Arrays.binarySearch(): 测试列子: public class MainTestArray { public static void main(String args[]){ String[] intArray = new String[]{"a","b","c","d","e","f","g&qu
查找某个字串出现的次数及位置 public class search { public static void main(String[] args){ String str = "abc123abcd1234"; String searchStr ="bc"; int count = getStrCount(str,searchStr); System.out.println("count is: "+ count); } public sta
package com.hanqi; import java.util.*; public class Test5 { public static void main(String[] args) { // TODO 自动生成的方法存根 //数组的二分查找法 //前提:数组要排好序 //1.随机生成生成数组 Random r1 = new Random(); int[] array = new int[10]; for (int i = 0; i < array.length; i++) { /