#include <bits/stdc++.h>
using namespace std;
#define endl '\n'
#define ll long long
#define len(s) (int)s.size()
#define int long long
#define pii pair<int, int>
#define fi first
#define se second
#define MASK(k) (1LL << (k))
int n, D, q;
const int MX = 3e5 + 5;
int C[MX], st[18][MX], ps[MX], f[MX], g[MX];
pii Q[MX];
int get(int l, int r){
int k = __lg(r - l + 1);
return min(st[k][l], st[k][r - MASK(k) + 1]);
}
namespace SUB1{
bool ok(){ return max(n, q) <= 3000; }
void solve(){
for(int i=1; i<=q; ++i){
int L, R; tie(L, R) = Q[i];
int sum = 0, ans = 0, pre = 0, last = 0;
for(int j=L; j<=R; ++j){
int x = C[j] % D;
if(x < pre) x += (((pre - x) / D) + 1) * D;
if(C[j] < x){
ans = -1;
break;
}
else ans += (C[j] - x);
pre = x, last = (C[j] - x);
}
cout << (ans == -1 ? ans : (ans - last * (R - L + 1)) / D) << endl;
}
exit(0); ///////////
}
}
namespace SUB3{
bool ok(){ return (D == 1); }
void solve(){
for(int i=1; i<=n;){
int cur = i;
while(C[i] == C[cur]) f[i] = cur, ++i;
}
for(int i=1; i<=n; ++i) st[0][i] = C[i], ps[i] = ps[i-1] + C[i];
for(int j=1; j<18; ++j){
for(int i=1; i+MASK(j-1)<=n; ++i){
st[j][i] = min(st[j-1][i], st[j-1][i + MASK(j-1)]);
}
}
for(int i=1; i<=q; ++i){
int L, R; tie(L, R) = Q[i];
R = max(L, f[R] - 1);
cout << (ps[R] - ps[L-1]) - get(L, R) * (R - L + 1) << endl;
}
exit(0); ///////
}
}
namespace SUB2{
bool ok(){
for(int i=1; i<=n; ++i) if(C[i] > 1) return 0;
return 1;
}
void solve(){
for(int i=1; i<=n;){
int cur = i;
while(C[i] == C[cur]) f[i] = cur, ++i;
}
for(int i=1; i<=n; ++i) ps[i] = ps[i-1] + C[i];
for(int i=1; i<=q; ++i){
int L, R; tie(L, R) = Q[i];
int sum = ps[R] - ps[L - 1];
if(C[R] == 0) cout << ((sum == 0 || D == 1) ? sum : -1) << endl;
else{
R = max(L, f[R] - 1);
sum = ps[R] - ps[L-1];
cout << ((sum == 0 || D == 1) ? sum : -1) << endl;
}
}
exit(0); /////////////
}
}
namespace SUB4{
bool ok(){
for(int i=1; i<n; ++i) if(C[i] < C[i+1]) return 0;
return 1;
}
void solve(){
int sum = 0, ans = 0, pre = 0, last = 0;
for(int j=1; j<=n; ++j){
int x = C[j] % D;
if(x < pre) x += (((pre - x) / D) + 1) * D;
f[j] = x;
pre = x, last = (C[j] - x);
ps[j] = ps[j-1] + C[j], g[j] = g[j-1] + f[j];
}
for(int i=1; i<=q; ++i){
int L, R; tie(L, R) = Q[i];
if(C[R] < f[R] - D*(f[L] / D)){
cout << -1 << endl;
continue;
}
int x = ps[R] - ps[L-1];
int y = g[R] - g[L-1] - (f[L] / D) * (R - L + 1);
int z = (C[R] - (f[R] - f[L] / D)) * (R - L + 1);
cout << (x - y - z) / D << endl;
}
exit(0); ////////////
}
}
int32_t main() {
ios_base::sync_with_stdio(0);
cin.tie(0);
cout.tie(0);
// freopen("main.inp","r",stdin);
// freopen("main.out","w",stdout);
cin >> n >> D;
for(int i=1; i<=n; ++i) cin >> C[i];
cin >> q;
for(int i=1; i<=q; ++i){
int L, R; cin >> L >> R;
Q[i] = {L, R};
}
// if(SUB3::ok()) SUB3::solve();
// if(SUB2::ok()) SUB2::solve();
// if(SUB1::ok()) SUB1::solve();
// SUB4::solve();
SUB3::solve();
return 0;
}
