题号：NC218908
时间限制：C/C++/Rust/Pascal 2秒，其他语言4秒
空间限制：C/C++/Rust/Pascal 256 M，其他语言512 M
64bit IO Format: %lld
时间限制：C/C++/Rust/Pascal 2秒，其他语言4秒
空间限制：C/C++/Rust/Pascal 256 M，其他语言512 M
64bit IO Format: %lld
题目描述
You are given a list of integers 
and a number k.
It is guaranteed that each i from 1 to k appears in the list at least once.Find the lexicographically smallest subsequence of x that contains
each integer from 1 to k exactly once.
输入描述:
The first line will contain two integers n and k, with.
The following n lines will each contain an integerwith
.
输出描述:
Write out on one line, separated by spaces, the lexicographically smallest
subsequence of x that has each integer from 1 to k exactly once.