算法的考查：数组的复制、反转、查找(线性查找、二分法查找)

算法的考查：数组的复制、反转、查找(线性查找、二分法查找

如下:

/* * 算法的考查：数组的复制、反转、查找(线性查找、二分法查找) * * */ public class ArrayTest2 { public static void main(String[] args) { String[] arr = new String[]{"xiaoMing","XIaoHuang","XiaoChen","XiaoLiu","XiaoYang","XiaoHong"}; //数组的复制(区别于数组变量的赋值：arr1 = arr) String[] arr1 = new String[arr.length]; for(int i = 0;i < arr1.length;i++){ arr1[i] = arr[i]; } //数组的反转 /*方法一： for(int i = 0;i < arr.length / 2;i++){ String temp = arr[i]; arr[i] = arr[arr.length - i -1]; arr[arr.length - i -1] = temp; } */ /*方法二： for(int i = 0,j = arr.length - 1;i < j;i++,j--){ String temp = arr[i]; arr[i] = arr[j]; arr[j] = temp; } */ //遍历 for(int i = 0;i < arr.length;i++){ System.out.print(arr[i] + "\t"); } System.out.println(); //查找（或搜索） //线性查找： String dest = "XiaoMing"; dest = "XiaoXi"; boolean isFlag = true; for(int i = 0;i < arr.length;i++){ if(dest.equals(arr[i])){ System.out.println("找到了指定的元素，位置为：" + i); isFlag = false; break; } } if(isFlag){ System.out.println("很遗憾，没有找到的啦！"); } //二分法查找：(熟悉) //前提：所要查找的数组必须有序。 int[] arr2 = new int[]{-123,-34,1,44,54,88,90,105,212,563}; int dest1 = -34; dest1 = 76; int head = 0;//初始的首索引 int end = arr2.length - 1;//初始的末索引 boolean isFlag1 = true; while(head <= end){ int middle = (head + end)/2; if(dest1 == arr2[middle]){ System.out.println("找到了指定的元素，位置为：" + middle); isFlag1 = false; break; }else if(arr2[middle] > dest1){ end = middle - 1; }else{//arr2[middle] < dest1 head = middle + 1; } } if(isFlag1){ System.out.println("很遗憾，没有找到的啦！"); } } }