//
// Created by adavy on 9/7/2025.
//
#include <bits/stdc++.h>
using namespace std;
using ll = long long;
int ssz = 524288;
vector<ll> seg(2*ssz, 0);
vector<ll> smin(2*ssz, -1);
vector<ll> lz(2*ssz, -1);
// range set range sum
void pushdown(int rt, int tl, int tr){
if (lz[rt] != -1){
seg[rt] = lz[rt] * (tr - tl + 1);
smin[rt] = lz[rt];
if (tl != tr){
lz[rt*2] = lz[rt];
lz[rt*2+1] = lz[rt];
}
lz[rt] = -1;
}
}
void add(ll x, int l, int r, int rt, int tl, int tr){
pushdown(rt, tl, tr);
if (tr < l || r < tl) return;
if (l <= tl && tr <= r){
lz[rt] = x;
pushdown(rt, tl, tr);
return;
}
int mid = (tl + tr) / 2;
add(x, l, r, rt*2, tl, mid);
add(x, l, r, rt*2+1, mid+1, tr);
seg[rt] = seg[rt*2] + seg[rt*2+1];
smin[rt] = max(smin[rt*2], smin[rt*2+1]);
}
ll sum(int l, int r, int rt, int tl, int tr){
pushdown(rt, tl, tr);
if (tr < l || r < tl) return 0;
if (l <= tl && tr <= r) return seg[rt];
int mid = (tl + tr) / 2;
return sum(l, r, rt*2, tl, mid) + sum(l, r, rt*2+1, mid+1, tr);
}
void find_split(int& split, ll sval, int rlim, int rt, int tl, int tr){
pushdown(rt, tl, tr);
if (tl == tr){
if (smin[rt] > sval) split = min(split, tl);
return;
}
int tm = (tl + tr) / 2;
if ( rlim < tm){
find_split(split, sval,rlim, rt*2, tl, tm);
return;
}
pushdown(rt*2, tl, tm);
if(smin[rt*2] > sval){
split = min(split, tm);
find_split(split, sval, rlim, rt*2, tl, tm);
} else {
find_split(split, sval, rlim, rt*2+1, tm+1, tr);
}
}
int main(){
int N; ll D;
cin >> N >> D;
vector<ll> h(N);
for(int i=0;i<N;++i) cin >> h[i];
vector<ll> d(N);
vector<ll> hprefs(N+1,0), dprefs(N+1,0);
d[N-1] = 0;
for(int i=N-1;i>=0;--i) {
d[i] = d[i+1] + (((h[i+1]-h[i])%D + D)%D);
}
// output d
//for (auto&x:d) cout << x << " ";
//cout << endl;
for(int i=0;i<N;++i){
hprefs[i+1] = hprefs[i] + h[i];
dprefs[i+1] = dprefs[i] + d[i];
}
vector<vector<pair<int,int>>>quers(N);
// left point, index
int Q; cin >> Q;
vector<ll> anses(Q, -1);
for(int i=0;i<Q;++i){
int l, r; cin >> l >> r; l--; r--;
quers[r].push_back( {l, i});
}
for(int r=0;r<N;++r){
// find the split point and update
// the split point is the first point in [0, r-1] more than h[i] + d[i]
ll sval = h[r] + d[r];
int split = r;
find_split(split, sval, r-1, 1, 0, ssz-1);
//cout << "r " << r << " split " << split << endl;
add(h[r]+d[r], split, r, 1, 0, ssz-1);
// now compute sums
for(auto q:quers[r]){
int l = q.first; int ind = q.second;
//cout << "lr " << l << " " << r << endl;
if (sum(l, l, 1, 0, ssz-1) < d[l]) {
anses[ind] = -1;
}
else {
anses[ind] = ((hprefs[r+1]-hprefs[l])-(sum(l, r, 1, 0, ssz-1) - (dprefs[r+1]-dprefs[l])))/D;
}
}
}
for(auto&a:anses) cout << a << endl;
}
