#include <iostream>
#include <vector>
#include <set>
#include <map>
#include <cstring>
#include <algorithm>
#include <stack>
#include <queue>
using namespace std;

const int MAX=2e5;

int n, q, niza[MAX + 1];
int segment_tree[3 * MAX + 1];

void build_tree(int L, int R, int position) {
    if(L == R) {
        segment_tree[position] = niza[L];
    }
    else {
        int middle = (L + R) / 2;
        build_tree(L, middle, 2 * position);
        build_tree(middle + 1, R, 2 * position + 1);
        segment_tree[position] = segment_tree[2 * position] ^ segment_tree[2 * position + 1];
    }
}
int query(int L, int R, int position, int i, int j) {
    // L R i L R j L R
    if(i <= L and R <= j) {
        return segment_tree[position];
    }
    if(R < i or j < L) {
        return 0;
    }
    int middle = (L + R) / 2;
    return query(L, middle, 2 * position, i, j) ^ query(middle + 1, R, 2 * position + 1, i, j);
}

int main() {
    ios_base::sync_with_stdio(false);
    cin.tie(0);
    
    cin >> n >> q;
    for (int i = 0; i < n; ++i) {
        cin >> niza[i];
    }
    build_tree(0, n - 1, 1);
    
    for(int i = 0; i < q; i++) {
        int a, b;
        cin >> a >> b;
        a--; b--;
        
        cout << query(0, n - 1, 1, a, b) << endl;
    }
}