Leetcode Find Minimum in Rotated Sorted Array

 1 package Find.Minimum.in.Rotated.Sorted.Array;
 2 
 3 /**
 4  * @author dell
 5  *运用二分查找法进行查找
 6  *查询效率为lgN
 7  */
 8 public class FindMinimuminRotatedSortedArray {
 9 public int findMin(int[] num) {
10       int lo=0;
11       int hi=num.length-1;
12       int mid=lo;
13       if(num.length==1) return num[0];
14       //可能出现将前面的第0个元素搬到后面，此时整个数组是递增有序的
15       //此时的情况是num[lo]<num[hi]
16     while(num[lo]>=num[hi]){
17         //当hi-lo=1时此时的hi为第二个递增数组的第一个元素，即为最小元素
18         if(hi-lo==1){
19             mid=hi;
20             break;
21         }
22        mid=(lo+hi)/2;
23        if(num[mid]<num[lo]) hi=mid;
24        else lo=mid;
25     }
26     return num[mid];
27     }
28 public static void main(String args[]){
29     FindMinimuminRotatedSortedArray service=new FindMinimuminRotatedSortedArray();
30     //int[] a={4,5,6,7,0,1,2};
31     int a[]={1,2};
32     int result=service.findMin(a);
33     System.out.println(result);
34 }
35 }