Submission #465392

#	Time	Username	Problem	Language	Result	Execution time	Memory
465392		a1415926	XORanges (eJOI19_xoranges)	C++14	100 / 100	662 ms	10516 KiB

xoranges

#include <iostream>
#include <vector>
#include <cmath>
using namespace std;
typedef vector<int> vi;
struct segtree {
    int len;
    vi a;
    void make(int n) {
        len = 1;
        while (len < n) len *= 2;
        a.resize(2 * len, 0);
    }
    void update(int ind, int val) {
        ind += len;
        a[ind] = val;
        ind /= 2;
        while (ind > 0) {
            a[ind] = a[2 * ind + 1] ^ a[2 * ind];
            ind /= 2;
        }
    }
    int query(int l, int r) {
        l += len, r += len;
        int ans = 0;
        while (r >= l) {
            if (l % 2 == 1) ans ^= a[l++];
            if (r % 2 == 0) ans ^= a[r--];
            l /= 2, r /= 2;
        }
        return ans;
    }
};
int main()
{
    int n, q, a_1, type, b_1, b_2;
    segtree seg1, seg2;
    cin >> n >> q;
    seg1.make(n);
    seg2.make(n);
    for (int i = 0; i < n; i++) {
        cin >> a_1;
        if (i % 2) seg1.update(i, a_1);
        else seg2.update(i, a_1);
    }
    for (int i = 0; i < q; i++) {
        cin >> type >> b_1 >> b_2;
        if (type == 1) {
            if ((b_1-1) % 2) seg1.update(b_1 - 1, b_2);
            else seg2.update(b_1 - 1, b_2);
        }
        if (type == 2) {
            if ((b_2 - b_1 - 1) % 2) {
                if ((b_1 - 1) % 2) cout << seg1.query(b_1 - 1, b_2 - 1) << "\n";
                else cout << seg2.query(b_1 - 1, b_2 - 1) << "\n";
            }
            else cout << 0 << "\n";
        }
    }
}

• Subtask 1: 12 / 12
• Subtask 2: 18 / 18
• Subtask 3: 25 / 25
• Subtask 4: 20 / 20
• Subtask 5: 25 / 25