/*
 * @lc app=leetcode id=33 lang=java
 *
 * [33] Search in Rotated Sorted Array
 */

// @lc code=start
class Solution {
    public int search(int[] nums, int target) {
        if(nums == null ||nums.length == 0) {
            return -1;
        }
        int r;
        if(target >= nums[0]) {
            // find in ascending side
            r = searchInAscendingSide(nums, target);
        } else {
            // find in descending side
            r = searchInDescendingSide(nums, target);
        }
        return r;
    }

    private int searchInAscendingSide(int[] nums, int target) {
        int l = 0, r = nums.length-1, m;
        while(l<=r) {
            m = l + (r-l)/2;
            if(nums[m] == target) {
                return m;
            } else if(!isAscendingSide(m, nums)) {
                r = m -1;
            } else if(nums[m] < target) {
                l = m + 1;
            } else {
                r = m -1;
            }
        }
        return -1;
    }

    private int searchInDescendingSide(int[] nums, int target) {
        int l = 0, r = nums.length-1, m;
        while(l <= r) {
            m = l + (r-l)/2;
            if(nums[m] == target) {
                return m;
            } else if(isAscendingSide(m, nums)) {
                l = m + 1;
            } else if(nums[m] < target) {
                l = m + 1;
            } else {
                r = m - 1;
            }
        }
        return -1;
    }

    private boolean isAscendingSide(int i, int[] nums) {
        return nums[i]>=nums[0];
    }
}
// @lc code=end