oj.uz

Submission #798336

# Submission time Handle Problem Language Result Execution time Memory
798336 2023-07-30T15:38:23 Z GrindMachine XOR Sum (info1cup17_xorsum) C++17
77 / 100
 1600 ms 8148 KB 
// Om Namah Shivaya

#pragma GCC optimize("O3,unroll-loops")
#pragma GCC target("avx2")

#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);

    auto get = [&](int l, int r){
        return upper_bound(all(b),r) - lower_bound(all(b),l);
    };

    int ans = 0;

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

        int ptr1 = n-1, ptr2 = n-1, ptr3 = n-1;

        ll cnt1 = 0, cnt2 = 0;
    
        rep(i,n){
            int x = b[i];
            while(ptr1 >= 0 and x+b[ptr1] >= f){
                ptr1--;
            }
            while(ptr2 >= 0 and x+b[ptr2] >= (f<<1)){
                ptr2--;
            }
            while(ptr3 >= 0 and x+b[ptr3] >= 3*f){
                ptr3--;
            }

            int lx = ptr1+1;
            int rx = ptr2;

            cnt1 += max(rx-lx+1,0);
            cnt1 += n-1-ptr3;

            if((x+x)&f){
                cnt1--;
                cnt2++;
            }

            // cnt1 += get(f-x,2*f-x-1);
            // cnt1 += get(3*f-x,4*f);
            // if((x+x)&f){
            //     cnt1--;
            //     cnt2++;
            // }
        }

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

        ans += (cnt&1)*f;
    }

    cout << ans << endl;
}

int main()
{
    fastio;

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

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

    return 0;
}

Compilation message

xorsum.cpp: In function 'void solve(int)':
xorsum.cpp:74:10: warning: variable 'get' set but not used [-Wunused-but-set-variable]
   74 |     auto get = [&](int l, int r){
      |          ^~~

Subtask #1
7.0 / 7.0

# Verdict Execution time Memory Grader output
1 Correct 8 ms 340 KB Output is correct
2 Correct 8 ms 340 KB Output is correct

Subtask #2
11.0 / 11.0

# Verdict Execution time Memory Grader output
1 Correct 626 ms 8144 KB Output is correct
2 Correct 573 ms 7608 KB Output is correct

Subtask #3
21.0 / 21.0

# Verdict Execution time Memory Grader output
1 Correct 626 ms 8144 KB Output is correct
2 Correct 573 ms 7608 KB Output is correct
3 Correct 1319 ms 8148 KB Output is correct
4 Correct 1280 ms 7936 KB Output is correct

Subtask #4
38.0 / 38.0

# Verdict Execution time Memory Grader output
1 Correct 8 ms 340 KB Output is correct
2 Correct 8 ms 340 KB Output is correct
3 Correct 213 ms 1108 KB Output is correct
4 Correct 218 ms 1108 KB Output is correct

Subtask #5
0 / 23.0

# Verdict Execution time Memory Grader output
1 Correct 8 ms 340 KB Output is correct
2 Correct 8 ms 340 KB Output is correct
3 Correct 626 ms 8144 KB Output is correct
4 Correct 573 ms 7608 KB Output is correct
5 Correct 1319 ms 8148 KB Output is correct
6 Correct 1280 ms 7936 KB Output is correct
7 Correct 213 ms 1108 KB Output is correct
8 Correct 218 ms 1108 KB Output is correct
9 Execution timed out 1674 ms 8068 KB Time limit exceeded
10 Halted 0 ms 0 KB -