Submission #4027349

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Source Code Expand

#include <bits/stdc++.h>
#define REP(i, n) for(int i = 0;i < n;i++)
#define REPR(i, n) for(int i = n;i >= 0;i--)
#define FOR(i, m, n) for(int i = m;i < n;i++)
#define FORR(i, m, n) for(int i = m;i >= n;i--)
#define SORT(v, n) sort(v, v+n);
#define VSORT(v) sort(v.begin(), v.end());
#define VRSORT(v) sort(v.rbegin(), v.rend());//vectorの降順ソート
#define ll long long
#define pb(a) push_back(a)
#define INF 1000000000
#define MOD 1000000007
using namespace std;
typedef pair<int, int> P;
typedef pair<ll, ll> LP;
typedef pair<int, P> PP;
typedef pair<ll, LP> LPP;

typedef vector<unsigned int>vec;
typedef vector<vec> mat;

typedef tuple<ll, int, int> T;

int dy[]={0, 0, 1, -1, 0};
int dx[]={1, -1, 0, 0, 0};




int main(){
  cin.tie(0);
  ios::sync_with_stdio(false);
  int n;cin>>n;
  int a,b;
  cin >>a>>b;
  int k;
  cin>>k;
  vector<int> P(n,0);
  P[a-1]++;P[b-1]++;
  REP(i,k){
    int p;cin>>p;p--;
    P[p]++;
    if(P[p]>1){
      cout<<"NO"<<endl;
      return 0;
    }
  }
  cout << "YES" << endl;
}

Submission Info

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