#include<bits/stdc++.h>
#include<ext/pb_ds/assoc_container.hpp>
#include<ext/pb_ds/tree_policy.hpp>
using namespace std;
using namespace __gnu_pbds;
typedef long long ll;
typedef long double ld;
#define pb push_back
#define pii pair<int, int>
#define pll pair<ll, ll>
#define st first
#define nd second
#define ordered_set tree<int, null_type, less<int>, rb_tree_tag, tree_order_statistics_node_update>
#define debug false
const int MAXN = 300 * 1000 + 17;
ll a[MAXN];
vector<pii> zap[MAXN];
ll twyn[MAXN];
ll ile[MAXN];
ll sprefile[MAXN];
ll spref[MAXN];
ll aktspref[MAXN];
vector<pii> s;
int main () {
ios::sync_with_stdio(0); cin.tie(0); cout.tie(0);
int n;
ll d;
cin >> n >> d;
for (int i = 1; i <= n; i ++) {
cin >> a[i];
}
int q, l, r;
cin >> q;
for (int i = 0; i < q; i ++) {
cin >> l >> r;
zap[r].pb({l, i});
}
for (int i = 1; i <= n; i ++) {
spref[i] = spref[i - 1] + a[i];
ile[i] = ile[i - 1] + ((((a[i] - a[i - 1]) % d) + d) % d);
sprefile[i] = sprefile[i - 1] + ile[i];
}
for (int i = 1; i <= n; i ++) {
int ind = i;
while (!s.empty() && a[s.back().nd] - ile[s.back().nd] >= a[i] - ile[i]) {
ind = s.back().st;
s.pop_back();
}
s.pb({ind, i});
ll dl = i - ind + 1;
aktspref[i] = aktspref[ind - 1] + dl * a[i] - (ile[i] * dl - (sprefile[i] - sprefile[ind - 1]));
for (auto x : zap[i]) {
int p = 0, k = int(s.size()), w;
while (p <= k) {
int sr = (p + k)/ 2;
if (s[sr].nd >= x.st) {
k = sr - 1;
w = sr;
} else {
p = sr + 1;
}
}
ll w2 = spref[i] - spref[x.st - 1];
w2 -= aktspref[i] - aktspref[s[w].nd];
ll dl = s[w].nd - x.st + 1;
w2 -= dl * a[s[w].nd] - (ile[s[w].nd] * dl - (sprefile[s[w].nd] - sprefile[x.st - 1]));
w2 /= d;
if (a[s[w].nd] - (ile[s[w].nd] - ile[x.st]) < 0) {
w2 = -1;
}
twyn[x.nd] = w2;
}
}
for (int i = 0; i < q; i ++) {
cout << twyn[i] << "\n";
}
return 0;
}
