407999: GYM102961 M Playlist

You are given a playlist of a radio station since its establishment. The playlist has a total of $$$n$$$ songs.

What is the longest sequence of successive songs where each song is unique?

The first input line contains an integer $$$n$$$: the number of songs.

The next line has $$$n$$$ integers $$$k_1,k_2,\dots,k_n$$$: the id number of each song.

Constraints:

• $$$1 \le n \le 2\cdot 10^5$$$
• $$$1 \le k_i \le 10^9$$$

Print the length of the longest sequence of unique songs.

8
1 2 1 3 2 7 4 2

5