📅  最后修改于: 2022-03-11 14:52:44.205000             🧑  作者: Mango
class Solution {
public int search(int[] nums, int target) {
int pivot = FindPivot(nums);
int a_pointer = 0;
int b_pointer = nums.length-1;
if (target >= nums[pivot] && target <= nums[b_pointer] ){
a_pointer = pivot;
}else{
b_pointer = pivot;
}
if (nums[a_pointer] == target) return a_pointer;
if (nums[b_pointer] == target) return b_pointer;
while(a_pointer <= b_pointer){
int midpoint = a_pointer + (b_pointer - a_pointer) / 2;
if (nums[midpoint] == target) return midpoint;
if (nums[midpoint] < target) a_pointer = midpoint + 1;
if (nums[midpoint] > target) b_pointer = midpoint - 1;
}
return -1;
}
public static int FindPivot(int[] nums){
int start = 0;
int end = nums.length-1;
while (start < end){
int mid = start + (end-start)/2;
if (nums[mid] > nums[end]){
start = mid+1;
}else end = mid;
}
return start;
}
}