#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, cnt[N];
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 {
for (int i = 1; i <= n; ++ i) ++ cnt[a[i]];
for (int i = 1; i <= 4e3; ++ i) {
for (int j = i; 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
*/
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
4 ms |
332 KB |
Output is correct |
2 |
Correct |
4 ms |
332 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Incorrect |
34 ms |
4204 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Incorrect |
34 ms |
4204 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
4 ms |
332 KB |
Output is correct |
2 |
Correct |
4 ms |
332 KB |
Output is correct |
3 |
Runtime error |
10 ms |
2080 KB |
Execution killed with signal 11 |
4 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
4 ms |
332 KB |
Output is correct |
2 |
Correct |
4 ms |
332 KB |
Output is correct |
3 |
Incorrect |
34 ms |
4204 KB |
Output isn't correct |
4 |
Halted |
0 ms |
0 KB |
- |