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用三段翻转法！！！
如[4,5,1,2,3],首先[5,4],然后[3,2,1],最后[1,2,3,4,5]

class Solution {
public:
    /**
     * @param nums: An integer array
     * @return: nothing
     */
    void recoverRotatedSortedArray(vector<int> &nums) {
        // write your code here
        int index = 0;
        int cur = 0;
        for(int i = 1; i < nums.size(); i++){
            if(nums[i] < nums[i-1]){
                index = i;
            }
        }
        int left;
        int right;
        left = 0, right = index - 1;
        while(right >= left){
            int tmp = nums[left];
            nums[left++] = nums[right];
            nums[right--] = tmp;
            
        }
        left = index, right = nums.size() - 1;
        while(right >= left){
            int tmp = nums[left];
            nums[left++] = nums[right];
            nums[right--] = tmp;
        }
        left = 0, right = nums.size() - 1;
        while(right >= left){
            int tmp = nums[left];
            nums[left++] = nums[right];
            nums[right--] = tmp;
        }
    }
};