Java递归算法——二分查找

时间:2023-03-09 04:39:22
Java递归算法——二分查找

Java递归算法——二分查找

import java.lang.reflect.Array;
import java.nio.Buffer;
import java.util.Arrays;
import java.util.Random; //=================================================
// File Name : RecFind
//------------------------------------------------------------------------------
// Author : Common //类名:BinarySearch_Find
//属性:
//方法:
class Rec_Find{
private int[] temp;
private int searchKey;
//private int lowerBound = 0; //下界
//private int upperBound ; //上界
private int nElement; public int[] getTemp() {
return temp;
} public void setTemp(int[] temp) {
this.temp = temp;
} public Rec_Find(int[] temp) {//构造函数
this.temp = temp;
//this.upperBound = temp.length-1;
} public int find(int searchKey,int lowerBound,int upperBound){
int curNum;
this.searchKey = searchKey;
curNum = (lowerBound+upperBound)/2;
if(temp[curNum]==this.searchKey){
return curNum; //find
}
else if(lowerBound>upperBound){
return -1; //没有find
}
else{
if(temp[curNum]<this.searchKey){
return find(searchKey,curNum+1,upperBound);
}
else{
return find(searchKey,lowerBound,curNum-1);
}
} } } //类名:RandomArrays
//属性:
//方法:
class RandomArray{ //生成随机数组,有Num个 private int[] Arrays; public int[] getArrays(int Num){
// int[] Arrays = new int[Num];
Arrays = new int[Num];
Random r = new Random(); for(int i=0;i<Num;i++){
Arrays[i] = r.nextInt(1000);
// System.out.print(Arrays[i]+"、");
}
return Arrays;
}
} //类名:OrderedArrays
//属性:
//方法:
class OrderedArray{ //生成有序数组,从0开始到Num public int[] getArrays(int Num){
int[] Arrays = new int[Num]; for(int i=0;i<Num;i++){
Arrays[i] = i;
// System.out.print(Arrays[i]+"、");
}
return Arrays;
}
} //主类
//Function : RecFind
public class RecFind { public static void main(String[] args) {
// TODO 自动生成的方法存根 // RandomArrays array_demo = new RandomArrays();
// BinarySearch_Find arrays = new BinarySearch_Find(array_demo.getArrays(100)); OrderedArray array_demo = new OrderedArray();
Rec_Find arrays = new Rec_Find(array_demo.getArrays(100));
System.out.println(Arrays.toString(arrays.getTemp()));
System.out.println(arrays.find(55,0,100));
} }