二分查找

使用二分查找：確保待查找的數組或者集合的數據是有序排列（升序或者降序）

話不多說，上代碼：

public class TwoFind {
    public static void main(String args[]){
    int searchData=89;
    //int dbArray[]={12,56,67,89,45,23,67,89,10};
        int dbArray[]={12,23,45,55,67,89,100};
    show(searchData,dbArray);
    }
    public static void show(int searchData,int dbArray[]){
     int start=0;
     int end=dbArray.length-1;
     int mid=0;
     while(start<=end){
          int temp=(start+end)%2;
           mid=(temp==0?(start+end)/2:(start+end)/2+1);
         //mid=(start+end)/2;
           if(searchData>dbArray[mid]){
             start=mid+1;
           }
           else if(searchData==dbArray[mid]){
            System.out.println("找到目標數據位置爲："+mid+" 數據爲："+dbArray[mid]);
            break;
           }
           else{
               end=mid-1;
           }
           System.out.println("!!!");
     }

    }

}

結果爲：

!!!
找到目標數據位置爲：5 數據爲：89

Process finished with exit code 0