#include<bits/stdc++.h>
using namespace std;
const int MAX = 3e5 + 5;
#define mod __mod
#define div __div
int n, q, bad[MAX];
long long D, a[MAX], mod[MAX], div[MAX], handle[MAX], pref[MAX];
vector<pair<int, int>> queries[MAX];
long long st[MAX << 2], lazy[MAX << 2], answer[MAX];
bool applied[MAX << 2];
void apply(int id, int l, int r, long long val){
st[id] = val * (r - l + 1);
lazy[id] = val;
applied[id] = true;
}
void pushDown(int id, int l, int r, int mid){
if(applied[id]){
apply(id << 1, l, mid, lazy[id]);
apply(id << 1 | 1, mid + 1, r, lazy[id]);
applied[id] = false;
lazy[id] = 0;
}
}
void update(int id, int l, int r, int u, int v, long long val){
if(u <= l && r <= v){
apply(id, l, r, val);
}
else{
int mid = l + r >> 1;
pushDown(id, l, r, mid);
if(u <= mid) update(id << 1, l, mid, u, v, val);
if(mid < v) update(id << 1 | 1, mid + 1, r, u, v, val);
st[id] = st[id << 1] + st[id << 1 | 1];
}
}
long long query(int id, int l, int r, int u, int v){
if(v < l || u > r) return 0;
if(u <= l && r <= v) return st[id];
int mid = l + r >> 1;
pushDown(id, l, r, mid);
return query(id << 1, l, mid, u, v) + query(id << 1 | 1, mid + 1, r, u, v);
}
int main(){
ios_base::sync_with_stdio(0);
cin.tie(0);
cin >> n >> D;
for(int i = 1; i <= n; ++i) {
cin >> a[i];
mod[i] = a[i] % D;
div[i] = a[i] / D;
if(mod[i - 1] > mod[i]) bad[i] = 1;
bad[i] = bad[i - 1] + bad[i]; //mod[i - 1] > mod[i]
handle[i] = div[i] - bad[i];
pref[i] = pref[i - 1] + handle[i];
}
cin >> q;
for(int i = 0; i < q; ++i){
int l, r;
cin >> l >> r;
queries[r].push_back({l, i});
}
stack<int> s;
for(int i = 1; i <= n; ++i){
while(!s.empty() && handle[s.top()] >= handle[i]){
s.pop();
}
update(1, 1, n, (s.empty() ? 1 : s.top() + 1), i, handle[i]);
s.push(i);
for(auto [j, id] : queries[i]){
long long minHandle = query(1, 1, n, j, j);
if(bad[j] + minHandle < 0) answer[id] = -1;
else answer[id] = pref[i] - pref[j - 1] - query(1, 1, n, j, i);
}
}
for(int i = 0; i < q; ++i){
cout << answer[i] << '\n';
}
return 0;
}
