在一个有序数组中,找某个数是否存在

package com.harrison.Class01;

import java.util.Arrays;

public class Code04_BSExist {
    
    
	public static boolean exist(int[] sortedArr,int num) {
    
    
		if(sortedArr==null || sortedArr.length==0) {
    
    
			return false;
		}
		int l=0;
		int r=sortedArr.length-1;
		int mid=0;
		while(l<r) {
    
    
			mid=l+((r-l)>>1);
			if(sortedArr[mid]==num) {
    
    
				return true;
			}else if(sortedArr[mid]>num) {
    
    
				r=mid-1;
			}else {
    
    
				l=mid+1;
			}
		}
		return sortedArr[l]==num;
	}
	
	public static boolean test(int[] sortedArr,int num) {
    
    
		for(int cur:sortedArr) {
    
    
			if(cur==num) {
    
    
				return true;
			}
		}
		return false;
	}
	
	public static int[] generateRandomArray(int maxSize,int maxValue) {
    
    
		int[] arr=new int[(int)(Math.random()*(maxSize+1))];
		for(int i=0; i<arr.length; i++) {
    
    
			arr[i]=(int)(Math.random()*(maxValue+1))-(int)(Math.random()*maxValue);
		}
		return arr;
	}
	
	public static void main(String[] args) {
    
    
		int testTimes=1000000;
		int maxSize=100;
		int maxValue=100;
		boolean succeed=true;
		for(int i=0; i<testTimes; i++) {
    
    
			int[] arr=generateRandomArray(maxSize, maxValue);
			Arrays.sort(arr);
			int num=(int)(Math.random()*(maxValue+1))-(int)(Math.random()*maxValue); 
			if(exist(arr, num)!=test(arr, num)) {
    
    
				succeed=false;
				break;
			}
		}
		System.out.println(succeed?"Nice":"Fucking fucked");
	}
}

Guess you like

Origin blog.csdn.net/weixin_44337241/article/details/121461840