Submission #1146480

#	Time	Username	Problem	Language	Result	Execution time	Memory
1146480		aliarapov	XOR Sum (info1cup17_xorsum)	C++20	11 / 100	243 ms	8260 KiB

xorsum

#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;

#define int long long
#define all(x) x.begin(),x.end() 
#define rall(x) x.rbegin(),x.rend()
           
template<class T, class U> inline bool chmin(T& a, const U& b) { if (a > b) { a = b; return true; } return false; }
template<class T, class U> inline bool chmax(T& a, const U& b) { if (a < b) { a = b; return true; } return false; } 

template <typename T>
using ordered_set = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;
 
template <typename T>
using ordered_multiset = tree<T, null_type, less_equal<T>, rb_tree_tag, tree_order_statistics_node_update>;     

void solve() {
    int n;
    cin >> n;
    vector<int> a(n);
    for (int &i : a) cin >> i;
    const int N = 8e3 + 1;
    bitset<N> bt;
    for (int i = 0; i < n; i++) bt[a[i]] = !bt[a[i]];
    bitset<N> ans;
    for (int i = 0; i < n; i++) {
        ans ^= bt << a[i];
        bt[a[i]] = !bt[a[i]];
    }
    int res = 0;
    for (int i = 0; i < N; i++) {
        if (ans[i]) res ^= i;
    }
    cout << res;
}

signed main() {
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);cout.tie(nullptr);

    int t = 1;
 //   cin >> t;
    while(t--){
        solve();
    }
}

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