#818257 (C++17) No.2126 MEX Game

• 問題: No.2126 MEX Game
• ユーザー: TKTYI
• 提出日時: 2022-11-19 05:16:12
• 言語: C++17 (gcc 12.3.0 + boost 1.83.0)
• 結果: AC
• 実行時間: 32 ms / 2,000 ms
• コード長: 2,507 bytes
• コンパイル時間: 4,642 ms
• コンパイル使用メモリ: 271,136 KB
• 実行使用メモリ: 5,376 KB
• 最終ジャッジ日時: 2024-09-20 08:08:50
• 合計ジャッジ時間: 6,034 ms
• ジャッジサーバーID （参考情報）: judge2 / judge1

入力	結果	実行時間; 実行使用メモリ
testcase_00	AC	2 ms; 5,248 KB
testcase_01	AC	2 ms; 5,376 KB
testcase_02	AC	2 ms; 5,376 KB
testcase_03	AC	2 ms; 5,376 KB
testcase_04	AC	2 ms; 5,376 KB
testcase_05	AC	2 ms; 5,376 KB
testcase_06	AC	2 ms; 5,376 KB
testcase_07	AC	2 ms; 5,376 KB
testcase_08	AC	2 ms; 5,376 KB
testcase_09	AC	2 ms; 5,376 KB
testcase_10	AC	30 ms; 5,376 KB
testcase_11	AC	30 ms; 5,376 KB
testcase_12	AC	30 ms; 5,376 KB
testcase_13	AC	30 ms; 5,376 KB
testcase_14	AC	31 ms; 5,376 KB
testcase_15	AC	31 ms; 5,376 KB
testcase_16	AC	31 ms; 5,376 KB
testcase_17	AC	24 ms; 5,376 KB
testcase_18	AC	26 ms; 5,376 KB
testcase_19	AC	18 ms; 5,376 KB
testcase_20	AC	17 ms; 5,376 KB
testcase_21	AC	32 ms; 5,376 KB
testcase_22	AC	2 ms; 5,376 KB
testcase_23	AC	1 ms; 5,376 KB
testcase_24	AC	2 ms; 5,376 KB
testcase_25	AC	2 ms; 5,376 KB
testcase_26	AC	2 ms; 5,376 KB
testcase_27	AC	2 ms; 5,376 KB
testcase_28	AC	2 ms; 5,376 KB
testcase_29	AC	2 ms; 5,376 KB

ソースコード

#include<bits/stdc++.h>
#include<atcoder/all>
using namespace std;
using namespace atcoder;
typedef long long int ll;
typedef long double ld;
#define FOR(i,l,r) for(ll i=l;i<r;i++)
#define REP(i,n) FOR(i,0,n)
#define RFOR(i,l,r) for(ll i=r-1;i>=l;i--)
#define RREP(i,n) RFOR(i,0,n)
#define ALL(x) x.begin(),x.end()
#define PA pair<ll,ll>
#define F first
#define S second
#define BS(A,x) binary_search(ALL(A),x)
#define LB(A,x) (ll)(lower_bound(ALL(A),x)-A.begin())
#define UB(A,x) (ll)(upper_bound(ALL(A),x)-A.begin())
#define COU(A,x) (UB(A,x)-LB(A,x))
#define sz(c) ((ll)(c).size())
/*
#include<boost/multiprecision/cpp_int.hpp>
namespace mp=boost::multiprecision;
using Bint=mp::cpp_int;
*/
template<typename T>using min_priority_queue=priority_queue<T,vector<T>,greater<T>>;
template<typename T1,typename T2>ostream&operator<<(ostream&os,pair<T1,T2>&p){os<<p.F<<" "<<p.S;return os;}
template<typename T1,typename T2>istream&operator>>(istream&is,pair<T1,T2>&p){is>>p.F>>p.S;return is;}
template<typename T>ostream&operator<<(ostream&os,vector<T>&v){REP(i,sz(v))os<<v[i]<<(i+1!=sz(v)?" ":"");return os;}
template<typename T>istream&operator>>(istream&is,vector<T>&v){for(T&in:v)is>>in;return is;}
template<class T>bool chmax(T&a,T b){if(a<b){a=b;return 1;}return 0;}
template<class T>bool chmin(T&a,T b){if(b<a){a=b;return 1;}return 0;}
ld dist(ld x1,ld y1,ld x2,ld y2){return sqrtl((x1-x2)*(x1-x2)+(y1-y2)*(y1-y2));}
void YN(bool x){cout<<(x?"Yes":"No")<<endl;}
//using mint=modint1000000007;
using mint=modint998244353;
//const ll mod=1000000007;
const ll mod=998244353;
//using mint=modint;
ostream&operator<<(ostream&os,mint&a){os<<a.val();return os;}

vector<ll>fast_mod_convolution(vector<ll>&a,vector<ll>&b,ll mod){
  const ll m1=167772161,m2=469762049,m3=1224736769;
  const ll m1_inv_m2=inv_mod(m1,m2);
  const ll m12_inv_m3=inv_mod(m1*m2,m3);
  const ll m12_mod=m1*m2%mod;
  auto x=convolution<m1>(a,b);
  auto y=convolution<m2>(a,b);
  auto z=convolution<m3>(a,b);
  vector<ll>ret(sz(a)+1);
  REP(i,sz(a)+1){
    ll v1=(y[i]-x[i])*m1_inv_m2%m2;if(v1<0)v1+=m2;
    ll v2=(z[i]-(x[i]+m1*v1)%m3)*m12_inv_m3%m3;if(v2<0)v2+=m3;
	ret[i]=(x[i]+m1*v1+m12_mod*v2)%mod;
  }
  return ret;
}

int main(){
  ll N;cin>>N;
  vector<ll>A(N+1);
  REP(i,N){ll a;cin>>a;if(a<=N)A[a]++;}
  bool a=1;
  REP(i,N+1){
      if(!A[i]){cout<<i<<endl;break;}
      if(A[i]==1){
          if(a&&2*i+2<=N)a=0;
          else{cout<<i<<endl;break;}
      }
      else if(!a&&2*i+1==N){cout<<i<<endl;break;}
  }
  return 0;
}