#include <iostream>
#include <algorithm> // for sort, mainly
#include <vector>
#include <map>
#include <set>
#include <cmath>
#include <array>
#include <string>
#include <cstdio>
#include <iterator>
#include <unordered_set>
#include <cstdint> // for int64_t, int32_t, etc
#include <queue>
#include <stack>
#include <deque>
#include <numeric> // gcd, lcm
#include <fstream>
#include <bitset> // for bitset
#include <iomanip>
#include <cassert> // for set with custom ordering
#include <type_traits> // for set with custom ordering
#include <utility> // for swap, forward, etc
using namespace std;

#pragma GCC optimize("O2")
// #pragma GCC optimize("O1","O2","O3","Ofast","unroll-loops")
//#pragma GCC target("sse","sse2","sse3","sse4.1","sse4.2","avx","avx2","fma")

template<typename A, typename B> ostream& operator<<(ostream &os, const pair<A, B> &p) { return os << '(' << p.first << ", " << p.second << ')'; }
template<typename T_container, typename T = typename enable_if<!is_same<T_container, string>::value, typename T_container::value_type>::type> ostream& operator<<(ostream &os, const T_container &v) { os << '{'; string sep; for (const T &x : v) os << sep << x, sep = ", "; return os << '}'; }
void dbg_out() { cout << endl; }
template<typename Head, typename... Tail> void dbg_out(Head H, Tail... T) { cout << ' ' << H; dbg_out(T...); }
#ifdef LOCAL
#define dbg(...) cout << "(" << #__VA_ARGS__ << "):", dbg_out(__VA_ARGS__)
#else
#define dbg(...)
#endif

/*
 *
 * notes:
 *
 * int64_t
 * stoi(string s) -> string to int
 * to_string() -> int (or else) to string
 *
 * vector declaration:
 * vector<ll> v(n, 0)
 * vector<vector<ll>> v(n, vector<ll>(n, 0));
 *
 * {if statement} ? {truth value} : {false value}
 *
 * set lower bound/upper bound:
 * 	// . . . m1 . . . d . . . . m2
 *    auto m1_it = b.lower_bound(d);
 *    advance(m1_it, -1);
 *    m1 = *m1_it;
 *	m2 = *b.upper_bound(d);
 *
 * #ifdef LOCAL
 *    freopen("in.txt","r",stdin);
 *    freopen("out.txt","w",stdout);
 * #endif
 *
 * constexpr auto lcm(auto x, auto... xs)
 * {
 *	return ((x = std::lcm(x, xs)), ...);
 * }
 *
 * std::gcd(int a, int b)
 *
 * cout << setprecision(n);
 *
 * set with custom ordering
 * set<ll, decltype(&cmp)> qu(cmp);
 *
 */

typedef int64_t ll;

void solve() {

    ll n, q;
    cin >> n >> q;

    ll inf = INT64_MAX;

    vector<ll> v(n, 0);
    vector<vector<ll>> gr(30, vector<ll>(30, inf));
    for(ll i = 0; i < 30; i++) {
        gr[i][i] = 0;
    }

    for(ll i = 0; i < n; i++) {
        vector<ll> temp;
        ll c;
        cin >> c;
        v[i] = c;
        ll counter = 0;
        while(c > 0) {
            ll md = c % 2;
            if(md == 1) {
                temp.push_back(counter);
            }
            counter++;
            c /= 2;
        }

        ll h = temp.size();
        for(ll j = 0; j < h; j++) {
            for(ll k = 0; k < h; k++) {
                if(j == k) {
                    continue;
                }
                
                gr[temp[j]][temp[k]] = 1;
                gr[temp[k]][temp[j]] = 1;

            }
        }
    }

    //cerr << "\nread in, graph init";

    // floyd-warshall
    for(ll k = 0; k < 30; k++) {
        for(ll i = 0; i < 30; i++) {
            for(ll j = 0; j < 30; j++) {
                if(gr[i][k] < inf && gr[k][j] < inf) {
                    gr[i][j] = min(gr[i][j], gr[i][k] + gr[k][j]);
                }
            }
        }
    }

    //cerr << "\nfloyd warshall";

    for(ll qi = 0; qi < q; qi++) {
        //cerr << "\nqi=" << qi;
        ll a, b;
        cin >> a >> b;
        a--;
        b--;

        if(a == b){
            cout << "0\n";
            return;
        }
        
        set<ll> af;
        set<ll> bf;
        ll c = v[a];
        ll counter = 0;
        while(c > 0) {
            ll md = c % 2;
            if(md == 1) {
                af.insert(counter);
            }
            counter++;
            c /= 2;
        }
        counter = 0;
        c = v[b];
        while(c > 0) {
            ll md = c % 2;
            if(md == 1) {
                bf.insert(counter);
            }
            counter++;
            c /= 2;
        }

        ll res = inf;

        for(const auto & ac : af) {
            for(const auto & bc : bf) {
                res = min(gr[ac][bc],res);
                res = min(gr[bc][ac],res);
            }
        }
        
        if(res == inf) {
            cout << "-1\n";
        }else{
            cout << res +1 << "\n";
        }

    }

}

int main()
{
    std::ios_base::sync_with_stdio(false);
    //cin.tie(nullptr);
    //cout.tie(nullptr);

    solve();

    return 0;
}