CF886B.Vlad and Cafes

Vlad likes to eat in cafes very much. During his life, he has visited cafes n times. Unfortunately, Vlad started to feel that his last visits are not any different from each other. To fix that Vlad had a small research.

First of all, Vlad assigned individual indices to all cafes. Then, he wrote down indices of cafes he visited in a row, in order of visiting them. Now, Vlad wants to find such a cafe that his last visit to that cafe was before his last visits to every other cafe. In other words, he wants to find such a cafe that he hasn't been there for as long as possible. Help Vlad to find that cafe.

弗拉德非常喜欢在咖啡馆用餐。他一生中总共去过咖啡馆 $n$ 次。不幸的是，弗拉德开始觉得他最近几次的访问彼此之间毫无区别。为了改善这种情况，弗拉德做了一项小研究。

首先，弗拉德为所有咖啡馆分配了唯一的编号。接着，他按访问顺序依次写下所去咖啡馆的编号。现在，弗拉德希望找出这样一家咖啡馆：他对该咖啡馆的最后一次访问，早于他对其他任意一家咖啡馆的最后一次访问。换言之，他希望找出这样一家咖啡馆：他距离上一次光顾它的时间最长。请帮助弗拉德找出这家咖啡馆。

In first line there is one integer n (1 ≤ n ≤ 2·105) — number of cafes indices written by Vlad.

In second line, n numbers _a_1, _a_2, ..., a__n (0 ≤ a__i ≤ 2·105) are written — indices of cafes in order of being visited by Vlad. Vlad could visit some cafes more than once. Note that in numeration, some indices could be omitted.

第一行包含一个整数 $n$（$1 \leq n \leq 2 \cdot 10^5$）—— 表示弗拉德记录的咖啡馆编号个数。

第二行包含 $n$ 个整数 $a_1,\ a_2,\ \dots,\ a_n$（$0 \leq a_i \leq 2 \cdot 10^5$）—— 表示弗拉德按访问顺序记录的咖啡馆编号。弗拉德可能多次访问同一间咖啡馆。注意：编号序列中可能存在空缺。

Print one integer — index of the cafe that Vlad hasn't visited for as long as possible.

输出一个整数——Vlad 最久未访问的咖啡馆的编号。

In first test, there are three cafes, and the last visits to cafes with indices 1 and 2 were after the last visit to cafe with index 3; so this cafe is the answer.

In second test case, there are also three cafes, but with indices 1, 2 and 4. Cafes with indices 1 and 4 were visited after the last visit of cafe with index 2, so the answer is 2. Note that Vlad could omit some numbers while numerating the cafes.

在第一个测试用例中，共有三家咖啡馆，编号为 1 和 2 的咖啡馆的最后一次访问均发生在编号为 3 的咖啡馆的最后一次访问之后；因此答案是咖啡馆 3。

在第二个测试用例中，同样有三家咖啡馆，但编号为 1、2 和 4。编号为 1 和 4 的咖啡馆的最后一次访问均发生在编号为 2 的咖啡馆的最后一次访问之后，因此答案是 2。注意：Vlad 在给咖啡馆编号时可能跳过某些数字。