oj.uz

Submission #496722

# Submission time Handle Problem Language Result Execution time Memory
496722 2021-12-22T03:24:52 Z armashka XOR Sum (info1cup17_xorsum) C++17
7 / 100
 951 ms 7596 KB 
#include <bits/stdc++.h>
 
//#pragma comment(linker, "/stack:200000000")
//#pragma GCC optimize("Ofast")
//#pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,tune=native")
 
#define fast ios_base::sync_with_stdio(false);cin.tie(nullptr);cout.tie(nullptr);
#define all(v) v.begin(),v.end()
#define pb push_back
#define sz size()
#define ft first
#define sd second
 
using namespace std;
typedef long long ll;
typedef pair<ll, ll> pll;
typedef unsigned long long ull;
 
const int N = 5e5 + 5;
const ll M = 1e8;
const ll inf = 1e18;
const ll mod = 1e9;
const double Pi = acos(-1); 
 
ll binpow(ll x, ll ti) { ll res = 1;while (ti){if(ti & 1)res *= x;x *= x;ti >>= 1; x %= mod; res %= mod;} return res;}
ll binmul(ll x, ll ti) { ll res = 0;while (ti){if(ti & 1)res += x;x += x;ti >>= 1; x %= mod; res %= mod;} return res;}
ll nok(ll a, ll b) { return (a*b)/__gcd(abs(a),abs(b)) * (a*b > 0 ? 1 : -1); }
bool odd(ll n) { return (n % 2 == 1); }
bool even(ll n) { return (n % 2 == 0); }            

ll n, a[N], ans;

const void solve(/*Armashka*/) {
	cin >> n;
	for (int i = 1; i <= n; ++ i) cin >> a[i];
	if (n <= 4e3) {
		for (int i = 1; i <= n; ++ i) {
			for (int j = i; j <= n; ++ j) ans ^= (a[i] + a[j]);
		}
	} else {
		map <ll, ll> cnt;
		for (int i = 1; i <= n; ++ i) ++ cnt[a[i]];
		for (int i = 1; i <= 4e3; ++ i) {
			for (int j = 1; j <= 4e3; ++ j) {
				if (odd(cnt[i] * cnt[j])) ans ^= (i + j);
			}
		}
	}
	cout << ans << "\n";
}
            
signed main() {
    fast;
    //freopen("divide.in", "r", stdin);
    //freopen("divide.out", "w", stdout);
    int tt = 1;
    //cin >> tt;
    while (tt --) {
        solve();
    }
}
 
/*
5 4 4
1 2
3 1
3 4
5 3
4 5 2 3
2 1 3 1
1 3 5
2 3 4 5
2 1 3 1
*/

Subtask #1
7.0 / 7.0

# Verdict Execution time Memory Grader output
1 Correct 5 ms 332 KB Output is correct
2 Correct 4 ms 332 KB Output is correct

Subtask #2
0 / 11.0

# Verdict Execution time Memory Grader output
1 Incorrect 42 ms 4176 KB Output isn't correct
2 Halted 0 ms 0 KB -

Subtask #3
0 / 21.0

# Verdict Execution time Memory Grader output
1 Incorrect 42 ms 4176 KB Output isn't correct
2 Halted 0 ms 0 KB -

Subtask #4
0 / 38.0

# Verdict Execution time Memory Grader output
1 Correct 5 ms 332 KB Output is correct
2 Correct 4 ms 332 KB Output is correct
3 Incorrect 951 ms 7596 KB Output isn't correct
4 Halted 0 ms 0 KB -

Subtask #5
0 / 23.0

# Verdict Execution time Memory Grader output
1 Correct 5 ms 332 KB Output is correct
2 Correct 4 ms 332 KB Output is correct
3 Incorrect 42 ms 4176 KB Output isn't correct
4 Halted 0 ms 0 KB -