제출 #798302

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
798302		GrindMachine	XOR Sum (info1cup17_xorsum)	C++17	7 / 100	1666 ms	8144 KiB

xorsum

// Om Namah Shivaya

#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>

using namespace std;
using namespace __gnu_pbds;

template<typename T> using Tree = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;
typedef long long int ll;
typedef long double ld;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;

#define fastio ios_base::sync_with_stdio(false); cin.tie(NULL)
#define pb push_back
#define endl '\n'
#define sz(a) a.size()
#define setbits(x) __builtin_popcountll(x)
#define ff first
#define ss second
#define conts continue
#define ceil2(x, y) ((x + y - 1) / (y))
#define all(a) a.begin(), a.end()
#define rall(a) a.rbegin(), a.rend()
#define yes cout << "Yes" << endl
#define no cout << "No" << endl

#define rep(i, n) for(int i = 0; i < n; ++i)
#define rep1(i, n) for(int i = 1; i <= n; ++i)
#define rev(i, s, e) for(int i = s; i >= e; --i)
#define trav(i, a) for(auto &i : a)

template<typename T>
void amin(T &a, T b) {
    a = min(a, b);
}

template<typename T>
void amax(T &a, T b) {
    a = max(a, b);
}

#ifdef LOCAL
#include "debug.h"
#else
#define debug(x) 42
#endif

/*



*/

const int MOD = 1e9 + 7;
const int N = 1e5 + 5;
const int inf1 = int(1e9) + 5;
const ll inf2 = ll(1e18) + 5;

void solve(int test_case)
{
    int n; cin >> n;
    vector<int> a(n);
    rep(i,n) cin >> a[i];

    int mx = *max_element(all(a));
    vector<int> b(n);

    int ans = 0;

    for(int f = 1; f <= 2*mx; f <<= 1){
        rep(i,n) b[i] = a[i]%(f<<1);
        sort(all(b));

        ll cnt = 0;

        rep(i,n){
            for(int j = i; j < n; ++j){
                int s = b[i]+b[j];
                if(s >= (f<<1)+f or (s >= f and s < 2*f)){
                    cnt++;
                }
            }
        }
        
        ans += (cnt&1)*f;

        // ll cnt1 = 0, cnt2 = 0;
        // int ptr = n-1;

        // rep(i,n){
        //     while(ptr >= 0 and b[i]+b[ptr] >= f){
        //         ptr--;
        //     }

        //     cnt1 += n-1-ptr;
        //     if(ptr < i){
        //         cnt1--;
        //         cnt2++;
        //     }
        // }

        // assert(!(cnt1&1));
        // ll tot = (cnt1>>1)+cnt2;

        // debug(tot);

        // int parity = tot&1;
        // ans |= f*parity;
    }

    cout << ans << endl;
}

int main()
{
    fastio;

    int t = 1;
    // cin >> t;

    rep1(i, t) {
        solve(i);
    }

    return 0;
}

• Subtask 1: 7 / 7
• Subtask 2: 0 / 11
• Subtask 3: 0 / 21
• Subtask 4: 0 / 38
• Subtask 5: 0 / 23