Submission #2124638

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Source Code Expand

#include<bits/stdc++.h>
#define REP(i,n) for(int i = 0;i < (n);i++)
#define P pair<int,int>
#define pb push_back
#define mk make_pair
using namespace std;
const int INF = 1 << 20;

typedef long long ll;




int main(){
  int n;
  cin >> n;
  vector <int> a;
  REP(i,n){
    int b;
    cin >> b;
    a.pb(b);
  }
  sort(a.begin(),a.end());
  int b = a[0],num = 1;
  for(int i = 1;i < a.size();i++){
    if(b == a[i]){
      num++;
      if(i == a.size()-1){
	if(num != 1 && num%2 == 1){
	  cout << i << num <<endl;
	  a.erase(a.begin()+i+1-num,a.begin()+i);
	}
      }
    }
    
    else{
      b = a[i];
      //cout << num << endl;
      if(num != 1 && num%2 == 1){
	a.erase(a.begin()+i-num,a.begin()+i-1);
	i = i - num+1;
      }
      else if(num != 1 && num != 2 && num%2 == 0){
	a.erase(a.begin()+i-num,a.begin()+i-2);
	i = i - num+2;
      }
      
      num = 1;
    }
  }
  b = a[0];
  num = 0;
  for(int i = 1;i < a.size();i++){
    if(a[i-1] == a[i])
      num++;
  }
  if(num%2 == 1)
    num++;
  int res = a.size()-num;
  cout << res << endl;
  /*
  REP(i,a.size()){
    cout << a[i] << "  ";
    }*/
  
  return 0;
}

Submission Info

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