Suppose an array sorted in ascending order is rotated at some pivot unknown to you beforehand.
(i.e., 0 1 2 4 5 6 7 might become 4 5 6 7 0 1 2).
You are given a target value to search. If found in the array return its index, otherwise return -1.
You may assume no duplicate exists in the array.
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| public class SearchInRotatedSortedArray {
public int search(int[] nums, int target) {
if (nums == null || nums.length == 0) return -1;
int l = 0;
int r = nums.length - 1;
while (l <= r) {
int m = l + (r - l) / 2;
if (nums[m] == target) return m;
if (nums[l] <= nums[m]) {
if (target >= nums[l] && target < nums[m]) {
r = m - 1;
} else {
l = m + 1;
}
} else {
if (target > nums[m] && target <= nums[r]) {
l = m + 1;
} else {
r = m - 1;
}
}
}
return -1;
}
}
|