Xor sum

#include <bits/stdc++.h>
using namespace std;

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

    vector<int> arr(n + 1);
    for (int i = 1; i <= n; i++) {
        int x;
        cin >> x;
        arr[i] = x;
    }
    vector<int> pre(n + 1);
    pre[1] = arr[1];
    for (int i = 2; i <= n; i++) {
        pre[i] = pre[i - 1] ^ arr[i];
    }

    vector<int> res;
    for (int i = 0; i < q; i++) {
        int a, b;
        cin >> a >> b;
        res.push_back(pre[a - 1] ^ pre[b]);
    }

    for (auto k : res) {
        cout << k << "\n";
    }
}

Test 1

Verdict: ACCEPTED

Test 2

Verdict: ACCEPTED