Submission #506961

#	Time	Username	Problem	Language	Result	Execution time	Memory
506961		armashka	XOR Sum (info1cup17_xorsum)	C++17	100 / 100	1057 ms	35592 KiB

xorsum

#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 = 1e6 + 10;
const ll M = 3e6;
const ll inf = 1e18;
const ll mod = 1e9 + 7;
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, ans;
vector <ll> v;

const void solve(/*Armashka*/) {
	cin >> n;
	for (int i = 1; i <= n; ++ i) {
		ll x; cin >> x;
		v.pb(x);	
	}
	for (int bit = 0; bit < 30; ++ bit) {
		vector <ll> a, b;
		for (auto x : v) {
			if (x & (1 << bit)) b.pb(x);
			else a.pb(x);
		}
		v.clear();
		for (auto x : a) v.pb(x);
		for (auto x : b) v.pb(x);

		ll cnt = 0, val = (1 << (bit + 1)) - 1;
		ll l, r; l = r = n - 1;
		for (int i = 0; i < n; ++ i) {
			while (l >= 0 && (v[i] & val) + (v[l] & val) >= (1 << bit)) -- l;
			while (r >= 0 && (v[i] & val) + (v[r] & val) >= (1 << (bit + 1))) -- r;
			cnt += max(0ll, r - max(l, i - 1ll));
		}
		l = r = n - 1;
		for (int i = 0; i < n; ++ i) {
			while (l >= 0 && (v[i] & val) + (v[l] & val) >= (1 << bit) * 3) -- l;
			while (r >= 0 && (v[i] & val) + (v[r] & val) >= (1 << (bit + 2))) -- r;
			cnt += max(0ll, r - max(l, i - 1ll));
		}
		if (odd(cnt)) ans ^= (1 << bit);
	}
	cout << ans << "\n";
}
            
signed main() {
    //fast;
    srand(time(NULL));
    //freopen("rmq.in", "r", stdin);
    //freopen("rmq.out", "w", stdout);
    int tt = 1;
    //cin >> tt;
    while (tt --) {                                                             
        solve();
    }
}
// Uaqyt, otedi, ketedi, mulde bilinbei ulger
// Kunder seni kutpeidi, susyz ospeidi gulder

Compilation message (stderr)

xorsum.cpp:3: warning: ignoring '#pragma comment ' [-Wunknown-pragmas]
    3 | #pragma comment(linker, "/stack:200000000")
      |

• Subtask 1: 7 / 7
• Subtask 2: 11 / 11
• Subtask 3: 21 / 21
• Subtask 4: 38 / 38
• Subtask 5: 23 / 23