Xor sum

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

string to_string(string s) {
    return '"' + s + '"';
}
 
string to_string(const char* s) {
    return to_string((string) s);
}
 
string to_string(bool b) {
    return (b ? "true" : "false");
}
 
template <typename A, typename B>
string to_string(pair<A, B> p) {
    return "(" + to_string(p.first) + ", " + to_string(p.second) + ")";
}
 
template <typename A>
string to_string(A v) {
    bool first = true;
    string res = "{";
    for (const auto &x : v) {
        if (!first) {
            res += ", ";
        }
        first = false;
        res += to_string(x);
    }
    res += "}";
    return res;
}
 
void debug_out() {
    cerr << endl;
}
 
template <typename Head, typename... Tail>
void debug_out(Head H, Tail... T) {
    cerr << " " << to_string(H);
    debug_out(T...);
}
 
#ifdef LOCAL
#define debug(...) cerr << "[" << #__VA_ARGS__ << "]:", debug_out(__VA_ARGS__)
#else
#define debug(...) 42
#endif

const int N = 1e5 + 5;

signed main() {
    cin.tie(0)->sync_with_stdio(0);

    int n, q;
    cin >> n >> q;

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

    while (q--) {
        int l, r;
        cin >> l >> r;
        cout << (p[r] ^ p[l - 1]) << '\n';
    }
}

Test 1

Verdict: ACCEPTED

Test 2

Verdict: ACCEPTED