oj.uz

Submission #270474

# Submission time Handle Problem Language Result Execution time Memory
270474 2020-08-17T16:18:56 Z egekabas XOR Sum (info1cup17_xorsum) C++14
45 / 100
 374 ms 131076 KB 
#include <bits/stdc++.h>
#define aint(x) (x).begin(), (x).end()
#define ff first
#define ss second
#define pb push_back
#define mp make_pair
using namespace std;
typedef long double ld;
typedef pair<int, int> pii;
typedef pair<ld, ld> pld;
int n, a[1000009];
pii v[32][1000009];
int ans = 0;
int main() {
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);
    
    //freopen("in.txt", "r", stdin);
    //freopen("out.txt", "w", stdout);

    cin >> n;
    for(int i = 0; i < n; ++i)
        cin >> a[i];
    for(int bit = 0; bit < 32; ++bit){
        int cur = 0;
        if(bit == 0){
            for(int i = 0; i < n; ++i)
                if(a[i]%2 == 0)
                    v[0][cur++] = {a[i], 0};
            for(int i = 0; i < n; ++i)
                if(a[i]%2)
                    v[0][cur++] = {a[i], 1};
        }
        else{
            for(int i = 0; i < n; ++i){
                pii u = v[bit-1][i];
                if((u.ff&(1<<bit)) == 0)
                    v[bit][cur++] = u;
            }
            for(int i = 0; i < n; ++i){
                pii u = v[bit-1][i];
                if((u.ff&(1<<bit)))
                    v[bit][cur++] = {u.ff, u.ss+(1<<bit)};
            }
        }
        int i1, i2, i3;
        i1 = i2 = i3 = n-1;
        int cnt = 0;
        for(int i = 0; i < n; ++i){
            i1 = max(i1, i-1);
            i2 = max(i2, i-1);
            i3 = max(i3, i-1);
            
            while(i1 >= i && v[bit][i].ss+v[bit][i1].ss >= (1<<bit))
                --i1;
            while(i2 >= i && v[bit][i].ss+v[bit][i2].ss >= (1<<(bit+1)))
                --i2;
            while(i3 >= i && v[bit][i].ss+v[bit][i3].ss >= (1<<(bit+1))+(1<<bit))
                --i3;
            
            cnt += i2-i1+n-1-i3;
        }
        if(cnt%2)
            ans += (1<<bit);
    }
    cout << ans << '\n';
}

Subtask #1
7.0 / 7.0

# Verdict Execution time Memory Grader output
1 Correct 4 ms 1664 KB Output is correct
2 Correct 5 ms 1664 KB Output is correct

Subtask #2
0 / 11.0

# Verdict Execution time Memory Grader output
1 Runtime error 374 ms 131076 KB Execution killed with signal 9
2 Halted 0 ms 0 KB -

Subtask #3
0 / 21.0

# Verdict Execution time Memory Grader output
1 Runtime error 374 ms 131076 KB Execution killed with signal 9
2 Halted 0 ms 0 KB -

Subtask #4
38.0 / 38.0

# Verdict Execution time Memory Grader output
1 Correct 4 ms 1664 KB Output is correct
2 Correct 5 ms 1664 KB Output is correct
3 Correct 95 ms 26104 KB Output is correct
4 Correct 88 ms 25976 KB Output is correct

Subtask #5
0 / 23.0

# Verdict Execution time Memory Grader output
1 Correct 4 ms 1664 KB Output is correct
2 Correct 5 ms 1664 KB Output is correct
3 Runtime error 374 ms 131076 KB Execution killed with signal 9
4 Halted 0 ms 0 KB -