oj.uz

Submission #1101051

# Submission time Handle Problem Language Result Execution time Memory
1101051 2024-10-15T12:33:46 Z Kirill22 XOR Sum (info1cup17_xorsum) C++17
45 / 100
 1600 ms 17148 KB 
#include "bits/stdc++.h"

using namespace std;

//#include "debug.h"

void solve() {
    int n;
    cin >> n;
    vector<int> a(n);
    for (int i = 0; i < n; i++) {
        cin >> a[i];
    }
    long long ans = 0;
    for (int bit = 0; bit < 31; bit++) {
        long long cnt = 0;
        vector<vector<int>> bucket(2);
        for (auto& x : a) {
            bucket[x >> bit & 1].push_back(x % (1 << bit));
        }
        std::sort(bucket[0].begin(), bucket[0].end());
        std::sort(bucket[1].begin(), bucket[1].end());
        for (auto [_, __] : vector<pair<int, int>>{{0, 0}, {1, 1}}) {
            auto l = bucket[_];
            auto r = bucket[__];
            int uk = 0;
            for (int i = (int) r.size() - 1; i >= 0; i--) {
                while (uk < (int) l.size() && l[uk] + r[i] < (1 << bit)) uk++;
                cnt += (int) l.size() - max(uk, i);
            }
        }
//        if (bit == 1) {
//            debug(bucket[0], bucket[1], cnt);
//        }
        for (auto [_, __] : vector<pair<int, int>>{{0, 1}}) {
            auto l = bucket[_];
            auto r = bucket[__];
            int uk = 0;
            for (int i = (int) r.size() - 1; i >= 0; i--) {
                while (uk < (int) l.size() && l[uk] + r[i] < (1 << bit)) uk++;
                cnt += uk;
            }
        }
        if (cnt % 2) {
            ans ^= (1 << bit);
        }
    }
    cout << ans << '\n';
}

int main() {
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);
    int t = 1;
//    cin >> t;
    while (t--) {
        solve();
    }
}

Subtask #1
7.0 / 7.0

# Verdict Execution time Memory Grader output
1 Correct 7 ms 336 KB Output is correct
2 Correct 7 ms 340 KB Output is correct

Subtask #2
0 / 11.0

# Verdict Execution time Memory Grader output
1 Execution timed out 1651 ms 17148 KB Time limit exceeded
2 Halted 0 ms 0 KB -

Subtask #3
0 / 21.0

# Verdict Execution time Memory Grader output
1 Execution timed out 1651 ms 17148 KB Time limit exceeded
2 Halted 0 ms 0 KB -

Subtask #4
38.0 / 38.0

# Verdict Execution time Memory Grader output
1 Correct 7 ms 336 KB Output is correct
2 Correct 7 ms 340 KB Output is correct
3 Correct 200 ms 3040 KB Output is correct
4 Correct 199 ms 3156 KB Output is correct

Subtask #5
0 / 23.0

# Verdict Execution time Memory Grader output
1 Correct 7 ms 336 KB Output is correct
2 Correct 7 ms 340 KB Output is correct
3 Execution timed out 1651 ms 17148 KB Time limit exceeded
4 Halted 0 ms 0 KB -