Submission #437446

#	Time	Username	Problem	Language	Result	Execution time	Memory
437446		MinhQNgo	XORanges (eJOI19_xoranges)	C++17	75 / 100	1081 ms	8704 KiB

xoranges

#include <bits/stdc++.h>

using namespace std;

const int N = 200005;

int a[N];
long long p[N];
int n;

void update() {
    int pos, val;
    cin >> pos >> val;
    a[pos] = val;
    p[1] = a[1];
    for (int i = 2; i <= n; i++) p[i] = p[i - 2] ^ a[i];
}

void query() {
    int l, r;
    cin >> l >> r;
    if ((r - l + 1) % 2 == 0) cout << 0 << '\n';
    else {
        cout << (p[r] ^ p[l] ^ a[l]) << '\n';
    }
}

int main() {
    ios_base::sync_with_stdio(0); cin.tie(0);

    int q;
    cin >> n >> q;
    for (int i = 1; i <= n; i++) {
        cin >> a[i];
        if (i == 1) p[i] = a[i];
        else p[i] = p[i - 2] ^ a[i];
    }
    for (int _ = 0; _ < q; _++) {
        int t;
        cin >> t;
        if (t == 1) update();
        else query();
    }
}

• Subtask 1: 12 / 12
• Subtask 2: 18 / 18
• Subtask 3: 25 / 25
• Subtask 4: 20 / 20
• Subtask 5: 0 / 25