// // Created by liasa on 25/01/2026. // #include <bits/stdc++.h> using namespace std; #define ll long long #define v vector #define lp(i, s, e) for (ll i = s; i < e; ++i) int main() { ios_base::sync_with_stdio(0); cin.tie(0); ll n, d; cin >> n >> d; v<ll> c(n); lp(i, 0, n) cin >> c[i]; v<ll> pre(n, 0), pref(n, 0); lp(i, 0, n) { if (c[i] == 1) pre[i] = (i == 0 ? 0 : pre[i - 1] + 1); pref[i] = (i == 0 ? 0 : pref[i - 1]) + c[i]; } ll q; cin >> q; while (q--) { ll l, r; cin >> l >> r; l--; r--; ll endi = pre[r]; endi = min(r - l + 1, endi); ll ones = pref[r] - (l == 0 ? 0 : pre[l - 1]); // cout<<ones<<" "; ll ans = ones - endi; // cout<<ans<<" "; if (d == 1) { cout << ans << '\n'; } else { if (ans == 0) { cout << 0 << '\n'; } else cout << -1 << '\n'; } } }