#include <bits/stdc++.h>
//#include "includeall.h"
//#include <ext/pb_ds/assoc_container.hpp>
//#include <ext/pb_ds/tree_policy.hpp>
#define endl '\n'
#define f first
#define s second
#define pb push_back
#define mp make_pair
#define lb lower_bound
#define ub upper_bound
#define input(x) scanf("%lld", &x);
#define input2(x, y) scanf("%lld%lld", &x, &y);
#define input3(x, y, z) scanf("%lld%lld%lld", &x, &y, &z);
#define input4(x, y, z, a) scanf("%lld%lld%lld%lld", &x, &y, &z, &a);
#define print(x, y) printf("%lld%c", x, y);
#define show(x) cerr << #x << " is " << x << endl;
#define show2(x,y) cerr << #x << " is " << x << " " << #y << " is " << y << endl;
#define show3(x,y,z) cerr << #x << " is " << x << " " << #y << " is " << y << " " << #z << " is " << z << endl;
#define all(x) x.begin(), x.end()
#define discretize(x) sort(x.begin(), x.end()); x.erase(unique(x.begin(), x.end()), x.end());
#define FOR(i, x, n) for (ll i =x; i<=n; ++i)
#define RFOR(i, x, n) for (ll i =x; i>=n; --i)
#pragma GCC optimize("O3","unroll-loops")
using namespace std;
mt19937_64 rnd(chrono::steady_clock::now().time_since_epoch().count());
//using namespace __gnu_pbds;
//#define ordered_set tree<int, null_type, less<int>, rb_tree_tag, tree_order_statistics_node_update>
//#define ordered_multiset tree<int, null_type, less_equal<int>, rb_tree_tag, tree_order_statistics_node_update>
typedef long long ll;
typedef long double ld;
typedef pair<ld, ll> pd;
typedef pair<string, ll> psl;
typedef pair<ll, ll> pi;
typedef pair<ll, pi> pii;
typedef pair<pi, pi> piii;
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
struct node{
int s, e, m;
ll val;
ll lazy;
node *l, *r;
node (int S, int E)
{
s = S, e = E, m = (s+e)/2;
val = 0;
lazy = 0;
l=r=nullptr;
}
void create()
{
if(s != e && l==nullptr)
{
l = new node(s, m);
r = new node(m+1, e);
}
}
void propogate()
{
if (lazy==0) return;
create();
val+=lazy*(e-s+1);
if (s != e){
l->lazy+=lazy;
r->lazy+=lazy;
}
lazy=0;
}
void update(int S, int E, ll V)
{
propogate();
if(s==S && e==E) lazy += V;
else{
create();
if(E <= m) l->update(S, E, V);
else if (m < S) r->update(S, E, V);
else l->update(S, m, V),r->update(m+1, E, V);
l->propogate(),r->propogate();
val = l->val + r->val;
}
}
ll query(int S, int E)
{
propogate();
if(s == S && e == E) return val;
create();
if(E <= m) return l->query(S, E);
else if(S >= m+1) return r->query(S, E);
else return l->query(S, m) + r->query(m+1, E);
}
} *root;
ll c[300005], ans[300005];
vector<pi> que[300005];
int main()
{
ll n, d, q;
cin >> n >> d;
root = new node(1, n);
for (ll i=1; i<=n; ++i) cin >> c[i];
cin >> q;
for (ll i=0; i<q; ++i)
{
ll l, r;
cin >> l >> r;
que[r].pb(mp(l, i));
}
deque<piii> dq;
for (ll i=1; i<=n; ++i)
{
//show(i);
while (dq.size() && dq.back().s.s > c[i])
{
ll idx1 = dq.back().f.f, idx2 = dq.back().f.s, lo = dq.back().s.f, hi = dq.back().s.s;
dq.pop_back();
ll take = (hi - c[i] + d-1)/d;
if (dq.size()) take = min(take, (lo - dq.back().s.s)/d);
lo -= d*take, hi -= d*take;
//show3(idx1, idx2, take);
root->update(idx1, idx2, take);
if (dq.size() && lo - dq.back().s.s < d) dq.back().f.s = idx2, dq.back().s.s = hi;
else dq.pb(mp(mp(idx1, idx2), mp(lo, hi)));
}
dq.pb(mp(mp(i, i), mp(c[i], c[i])));
for (pi u: que[i])
{
if (c[u.f] < root->query(u.f, u.f)*d) ans[u.s] = -1;
else ans[u.s] = root->query(u.f, i);
}
}
for (ll i=0; i<q; ++i) cout << ans[i] << endl;
return 0;
}
