Submission #773689

#	Time	Username	Problem	Language	Result	Execution time	Memory
773689		serifefedartar	XORanges (eJOI19_xoranges)	C++17	100 / 100	305 ms	11224 KiB

xoranges

#include <bits/stdc++.h>

using namespace std;

#define fast ios::sync_with_stdio(0);cin.tie(0);
typedef long long ll;
#define mod 1000000007
#define MAXN 200005

vector<int> arr;
pair<int,int> sg[4*MAXN];

void init(int k, int a, int b) {
    if (a == b) {
        if (a % 2 == 0)
            sg[k] = {arr[a], 0};
        else
            sg[k] = {0, arr[a]};
        return ;
    }
    init(2*k, a, (a+b)/2);
    init(2*k+1, (a+b)/2+1, b);
    sg[k] = {sg[2*k].first ^ sg[2*k+1].first, sg[2*k].second ^ sg[2*k+1].second};
}

void point_update(int k, int a, int b, int plc, int val) {
    if (plc > b || plc < a)
        return ;
    if (a == b) {
        if (a % 2 == 0)
            sg[k] = {val, 0};
        else
            sg[k] = {0, val};
        return ;
    }

    point_update(2*k, a, (a+b)/2, plc, val);
    point_update(2*k+1, (a+b)/2+1, b, plc, val);
    sg[k] = {sg[2*k].first ^ sg[2*k+1].first, sg[2*k].second ^ sg[2*k+1].second};
}

pair<int,int> query(int k, int a, int b, int q_l, int q_r) {
    if (q_r < a || q_l > b)
        return {0, 0};
    if (q_l <= a && b <= q_r)
        return sg[k];

    pair<int,int> p1 = query(2*k, a, (a+b)/2, q_l, q_r);
    pair<int,int> p2 = query(2*k+1, (a+b)/2+1, b, q_l, q_r);
    return {p1.first ^ p2.first, p1.second ^ p2.second};
}

int main() {
    fast
    int n, q;
    cin >> n >> q;

    arr = vector<int>(n+1);
    for (int i = 1; i <= n; i++)
        cin >> arr[i];
    init(1, 1, n);

    while (q--) {
        int t, i, j;
        cin >> t >> i >> j;
        if (t == 1) {
            point_update(1, 1, n, i, j);
        } else {
            if ((j - i + 1) % 2 == 0)
                cout << 0 << endl;
            else {
                if (i % 2 == 0)
                    cout << query(1, 1, n, i, j).first << endl;
                else
                    cout << query(1, 1, n, i, j).second << endl;
            }
        }
    }
}

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