Submission #3602672

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Source Code Expand

#include <bits/stdc++.h>
#define rep(i,a,b) for(int i=a;i<(b);++i)
#define erep(i,a,b) for(int i=a;i<=(int)(b);++i)
#define per(i,a,b) for(int i=(a);i>(b);--i)
#define eper(i,a,b) for(int i=(a);i>=b;--i)
#define fore(x, a) for(auto &x : a)
#define pb push_back
#define mp make_pair
#define INF 100100100100
#define inf 2001001001
#define MOD 1000000007
#define ALL(x) begin(x),end(x)
using namespace std;
using ll = long long;
using pii = pair<int,int>;
using vii = vector<int>;
using vll = vector<ll>;
template<class T>using vv = vector<T>;
template<class T>bool chmax(T &a, const T &b) { if (a<b) { a = b; return 1; } return 0; }
template<class T>bool chmin(T &a, const T &b) { if (b<a) { a = b; return 1; } return 0; }
template<class T>void show(const vector<T> &a) { for (int i = 0; i < (int)a.size(); ++i) cout << a[i] << (i != (int)a.size()-1 ? " " : "\n"); }
template<class T>T gcd(T a, T b){ return b ? gcd(b, a % b) : a; }
template<class T>T lcm(T a, T b){ return a / gcd(a, b) * b; }
int dy[]={0, 1, -1, 0};
int dx[]={1, 0, 0, -1};

ll n;
vll a;
int main() {
  cin.tie(0);
  ios::sync_with_stdio(false);
    cin >> n;
    a.resize(n);
    rep(i, 0, n) cin >> a[i];
    sort(ALL(a));
    bool flag = true;
    rep(i, 0, n) {
      if (n % 2) {
        flag = (i == 0 && a[i] == 0) ? true : false;
        if (i % 2) {
          flag = (a[i] == a[i+1] ? true : false); 
          i++;
        }
      } else {
        flag = (a[i] == a[i+1] ? true : false);
        i++;
      }
    }
    if (flag) cout << (n % 2 ? (n - 1) : n * 2) << endl;
    else cout << 0 << endl;
    return 0;
}

Submission Info

Judge Result