/**
* 二分查询
* @author DUSTDAWN
* n*(1/2)^x=1,时间复杂度x=log2 n
*/
public class Solution_1 {
public static void main(String[] args) {
int nums[] = {-1,0,3,9,5,12};
System.out.println(search(nums,3));
System.out.println(search(nums,4));
}
public static int search(int nums[],int target) {
int mid;
int left = 0;
int right = nums.length-1;
while(left <= right) {
mid = (left+right)/2;
if(target > nums[mid]) {
left = mid+1;
}else if(target <nums[mid]) {
right = mid-1;
}else
return mid;
}
return -1;
}
}