该程序使用二分搜索算法来在列表中搜索给定元素。
/* Program: Binary Search Example * Written by: Chaitanya from beginnersbook.com * Input: Number of elements, element's values, value to be searched * 输出：Position of the number input by user among other numbers*/import java.util.Scanner;class BinarySearchExample{ public static void main(String args[]) { int counter, num, item, array[], first, last, middle; //To capture user input Scanner input = new Scanner(System.in); System.out.println("Enter number of elements:"); num = input.nextInt(); //Creating array to store the all the numbers array = new int[num]; System.out.println("Enter " + num + " integers"); //Loop to store each numbers in array for (counter = 0; counter < num; counter++) array[counter] = input.nextInt(); System.out.println("Enter the search value:"); item = input.nextInt(); first = 0; last = num - 1; middle = (first + last)/2; while( first <= last ) { if ( array[middle] < item ) first = middle + 1; else if ( array[middle] == item ) { System.out.println(item + " found at location " + (middle + 1) + "."); break; } else { last = middle - 1; } middle = (first + last)/2; } if ( first > last ) System.out.println(item + " is not found.\n"); }}
输出 1：
Enter number of elements:7Enter 7 integers4566778990Enter the search value:7777 found at location 4.
输出 2：
Enter number of elements:5Enter 5 integers1237789023Enter the search value:9999 is not found.
