Language: C++

#include <bits/stdc++.h>
using namespace std;
#ifndef ONLINE_JUDGE
	#include <boost/multiprecision/cpp_int.hpp>
	#include <boost/multiprecision/cpp_dec_float.hpp>
	using bll = boost::multiprecision::cpp_int;
	using bdouble = boost::multiprecision::cpp_dec_float_100;
#endif
#ifdef LOCAL_DEV
	void debug_impl() { std::cerr << std::endl; }
	template<typename Head, typename... Tail> void debug_impl(Head head, Tail... tail) { std::cerr << " " << head << (sizeof...(tail) ? "," : ""); debug_impl(tail...); }
	#define debug(...) std::cerr << std::boolalpha << "(" << #__VA_ARGS__ << ") ="; debug_impl(__VA_ARGS__); std::cerr << std::noboolalpha;
#else
	#define debug(...)
#endif
#ifdef LOCAL_TEST
	#define BOOST_STACKTRACE_USE_ADDR2LINE
	#define BOOST_STACKTRACE_ADDR2LINE_LOCATION /usr/local/opt/binutils/bin/addr2line
	#define _GNU_SOURCE
	#include <boost/stacktrace.hpp>
	template<typename T> class dvector : public std::vector<T> {
	public:
		dvector() : std::vector<T>() {}
		explicit dvector(size_t n, const T& value = T()) : std::vector<T>(n, value) {}
		dvector(const std::vector<T>& v) : std::vector<T>(v) {}
		dvector(const std::initializer_list<T> il) : std::vector<T>(il) {}
		dvector(const typename std::vector<T>::iterator first, const typename std::vector<T>::iterator last) : std::vector<T>(first, last) {}
		dvector(const std::string::iterator first, const std::string::iterator last) : std::vector<T>(first, last) {}
		template<typename sizetype> T& operator[](sizetype n) {
			try { return this->at((size_t)n); } catch (const std::exception& e) {
				std::cerr << boost::stacktrace::stacktrace() << std::endl; return this->at((size_t)n);
			}
		}
		template<typename sizetype> const T& operator[](sizetype n) const {
			try { return this->at((size_t)n); } catch (const std::exception& e) {
				std::cerr << boost::stacktrace::stacktrace() << std::endl; return this->at((size_t)n);
			}
		}
	};
	class dbool {
	private:
		bool boolvalue;
	public:
		dbool() : boolvalue(false) {}
		dbool(bool b) : boolvalue(b) {}
		dbool(const dbool &b) : boolvalue(b.boolvalue) {}
		operator bool&() { return boolvalue; }
		operator const bool&() const { return boolvalue; }
	};
	template<typename T> std::ostream& operator<<(std::ostream& s, const dvector<T>& v) {
		for (int i = 0, len = v.size(); i < len; ++i){ s << v[i]; if (i < len - 1) s << "\t"; } return s; }
	template<typename T> std::ostream& operator<<(std::ostream& s, const dvector< dvector<T> >& vv) {
		for (int i = 0, len = vv.size(); i < len; ++i){ s << vv[i] << std::endl; } return s; }
	template<typename T> std::ostream& operator<<(std::ostream& s, const std::set<T>& se) {
		s << "{ "; for (auto itr = se.begin(); itr != se.end(); ++itr){ s << (*itr) << "\t"; } s << "}" << std::endl; return s; }
	template<typename T> std::ostream& operator<<(std::ostream& s, const std::multiset<T>& se) {
		s << "{ "; for (auto itr = se.begin(); itr != se.end(); ++itr){ s << (*itr) << "\t"; } s << "}" << std::endl; return s; }
	template<typename T1, typename T2> std::ostream& operator<<(std::ostream& s, const std::map<T1, T2>& m) {
		s << "{" << std::endl; for (auto itr = m.begin(); itr != m.end(); ++itr){ s << "\t" << (*itr).first << " : " << (*itr).second << std::endl; } s << "}" << std::endl; return s; }
	template<typename T1, typename T2> std::ostream& operator<<(std::ostream& s, const std::pair<T1, T2>& p) { 
		return s << "(" << p.first << ", " << p.second << ")"; }
	#define vector dvector
	#define bool dbool
	class SIGFPE_exception : std::exception {};
	class SIGSEGV_exception : std::exception {};
	void catch_SIGFPE(int e) { std::cerr << boost::stacktrace::stacktrace() << std::endl; throw SIGFPE_exception();	}
	void catch_SIGSEGV(int e) { std::cerr << boost::stacktrace::stacktrace() << std::endl; throw SIGSEGV_exception(); }
	signed convertedmain();
	signed main(){ signal(SIGFPE, catch_SIGFPE); signal(SIGSEGV, catch_SIGSEGV); convertedmain(); return 0;	}
	#define main() convertedmain()
#endif
//#define int long long
using ll = long long;
//constexpr int INF = 1e9;//INT_MAX=(1<<31)-1=2147483647
constexpr ll INF = (ll)1e18;//(1LL<<63)-1=9223372036854775807
constexpr ll MOD = (ll)1e9 + 7;
constexpr double EPS = 1e-9;
constexpr int dx[4] = {1, 0, -1, 0};
constexpr int dy[4] = {0, 1, 0, -1};
#define p(var) std::cout<<var<<std::endl
#define rep(i, n)   for(ll i=0, i##_length=(n); i< i##_length; ++i)
#define repeq(i, n) for(ll i=1, i##_length=(n); i<=i##_length; ++i)
#define all(v) (v).begin(), (v).end()
#define uniq(v) (v).erase(unique((v).begin(), (v).end()), (v).end());
template<typename T> inline void pv(vector<T> &v) { for(ll i=0, N=v.size(); i<N; i++) std::cout << v[i] << " \n"[i==N-1]; }
template<typename T> inline T gcd(T a, T b) { return b ? gcd(b,a%b) : a; }
template<typename T> inline T lcm(T a, T b) { return a / gcd(a,  b) * b; }
template<typename T1, typename T2> inline bool chmax(T1 &a, T2 b) { return a < b && (a = b, true); }
template<typename T1, typename T2> inline bool chmin(T1 &a, T2 b) { return a > b && (a = b, true); }

/*-----8<-----template-----8<-----*/

/*
set_next(k, x): 値kに1回操作を行うとxへ変化するよう設定する
build(): ダブリングを構築する
query(k, t): 値kにt回操作を行ったときの値を返却する
*/
class Doubling {
public:
	const ll LOG;
	vector< vector< ll > > table;
	
	Doubling(ll sz, ll lim_t) : LOG(64 - __builtin_clzll(lim_t)) {
		table.assign(LOG, vector< ll >(sz, -1));
	}

	void set_next(ll k, ll x) {
		table[0][k] = x;
	}

	void build() {
		for(ll k = 0; k + 1 < LOG; k++) {
			for(ll i = 0, size = table[k].size(); i < size; i++) {
				if(table[k][i] == -1) table[k + 1][i] = -1;
				else table[k + 1][i] = table[k][table[k][i]];
			}
		}
	}

	ll query(ll k, ll t) {
		for(ll i = LOG - 1; i >= 0; i--) {
			if((t >> i) & 1) k = table[i][k];
		}
		return k;
	}
};

/*-----8<-----library-----8<-----*/

const ll N_MAX = 2*1e5;
const ll K_MAX = 1e12;
const ll A_I_MAX = 2*1e5;

ll N, K;
vector<ll> A;

void solve() {
	scanf("%lld%lld", &N, &K);
	A.assign(N, 0);
	rep(i, N) scanf("%lld", &A[i]);

	vector<ll> AA(2*N,0);
	rep(i,2)rep(j,N)AA[N*i+j]=A[j];

	vector<vector<ll>> index(200001);
	rep(i,2*N){
		index[AA[i]].push_back(i);
	}
	//debug(index);

	debug((log2(K)+log2(N))+1);
	vector<vector<bll>> doubling((log2(K)+log2(N))+1,vector<bll>(N,0));
	rep(i,N){
		ll t=lower_bound(all(index[A[i]]),i)-index[A[i]].begin();
		doubling[0][i]=1+index[A[i]][t+1]-index[A[i]][t];
	}
	repeq(k,doubling.size()-1){
		rep(i,N){
			//debug(k,i,(i+doubling[k-1][i])%N);
			//if(i>52){debug(doubling[k-1][i],doubling[k-1][(i+doubling[k-1][i])%N]);}
			doubling[k][i]=doubling[k-1][i]+doubling[k-1][(i+doubling[k-1][i])%N];
		}
	}
	//debug(doubling);

	bll nokori=N*K;
	ll i=0;
	while(nokori>0){
		ll k=doubling.size()-1;
		while(k>=0 && nokori-doubling[k][i]<0){debug(nokori-doubling[k][i]);k--;}
		if(k<0){break;}
		nokori-=doubling[k][i];
		i=((ll)(i+doubling[k][i]))%N;
		debug(nokori);
		debug(i);
	}
	
	debug(nokori);
	debug(i);	
	vector<ll> stacked(200001, -1);
	vector<ll> v;
	while(i<N){
		if(stacked[A[i]]==-1){
			v.push_back(A[i]);
		}else{
			//rep(t,i-stacked[A[i]]){
			while(v[v.size()-1]!=A[i]){
				stacked[v[v.size()-1]]=-1;
				v.pop_back();
			}
			v.pop_back();
			stacked[A[i]]=-1;
		}
		i++;	
	}
	/*
	while(i<N){
		if(A[i]==1611){debug(i,stacked[A[i]])};
		if(stacked[A[i]]==-1){
			v.push_back(A[i]);
			//v[vindex]=A[i];
			//vindex++;
			stacked[A[i]]=i;
			//debug(1,vindex);
		}else{
			//debug(v.size(),i,stacked[A[i]],vindex);
			//debug(A[i],v);
			debug(A[i],v[v.size()-i+stacked[A[i]]]);
			rep(t,i-stacked[A[i]]){
				stacked[v[v.size()-1]]=-1;
				v.pop_back();
			}
			//v.pop_back();
			//debug(A[i],v[v.size()-1]);
			stacked[A[i]]=-1;
			//debug(2,v.size());
			//debug(v.size(),i,stacked[A[i]],vindex);
		}
		i++;
	}
	*/
	pv(v);

}

// https://atcoder.jp/contests/agc036/tasks/agc036_b
signed main() {
	solve();
	return 0;
}


Compiler output:
a.cc:4:18: fatal error: boost/multiprecision/cpp_int.hpp: No such file or directory
    4 |         #include <boost/multiprecision/cpp_int.hpp>
      |                  ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
compilation terminated.