经典算法之折半查找

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package 折半查找;   import java.util.Scanner;   public class BinarySearch {       /**      * 折半查找：要求查找的数据是线性保存，表中的数据是按照从小到大的顺序排列的      */           public static int source[] = {6,12,28,37,54,65,69,83,90,92};           public static int binarySearch(int s[],int n,int key){         int low,high,mid;         low = 0;         high = n-1;         while (low <= high) {             mid = (low+high)/2;             if (s[mid] == key) {                 return mid;             } else if (s[mid] > key) {                 high = mid-1;             } else {                 low = mid+1;             }                       }                   return -1;     }     public static void main(String[] args) {         Scanner input = new Scanner(System.in);         System.out.println("请输入关键字");         int key = input.nextInt();         int pos = binarySearch(source, source.length, key);         System.out.println("输出原始数据：");         for (int i = 0;i<source.length;i++) {             System.out.printf("%d\t",source[i]);         }         System.out.println();                   if (pos >= 0) {             System.out.printf("查找成功，该关键字位于数组的第%d个位置\n",pos);         }else{             System.out.println("查找失败！");         }               }                                                 }