Xor sum

#include <bits/stdc++.h>
 
using namespace std;
 
 
const int MAX_N = 2e5;
 
 
 
int main() {
    int n, q, arr[MAX_N + 1], prefix[MAX_N + 1], a, b;
 
	//ios_base::sync_with_stdio(false);
 
	//cin.tie(0);
 
 
	cin >> n >> q;
 
	// arr and prefix use 1-based indexing
 
	for (int i = 1; i <= n; ++i) 
        cin >> arr[i];
	prefix[1] = arr[1];
	for (int i = 2; i <= n; i++)
        prefix[i] = prefix[i - 1] ^ arr[i];
 
	while (q--) {
		cin >> a >> b;
		cout << (prefix[a - 1] ^ prefix[b]) << endl;
	}
 
}

Test 1

Verdict: ACCEPTED

Test 2

Verdict: ACCEPTED