#include<bits/stdc++.h>
using namespace std;
vector<long long> haha(300001);
vector<long long> wow(1200001);
vector<long long> bruh[12000001];
vector<long long> yay[1200001];
vector<long long> yeah[1200001];
long long sm = LLONG_MAX,ans = 0,d;
void build(long long l, long long r, long long x) {
bruh[x].push_back(LLONG_MAX);
yay[x].push_back(0);
yeah[x].push_back(0);
long long sb = 0,br = 0;
for(long long i = r; i >= l; i--) {
long long c = bruh[x][bruh[x].size()-1];
long long f = 0;
if(c < haha[i]) {
f = (haha[i]-c+d-1)/d;
}
wow[x]+=f;
bruh[x].push_back(haha[i]-f*d);
long long e = haha[i]-f*d;
if(c != LLONG_MAX) {
br+=(c-e)/d;
}
yay[x].push_back(br);
sb+=br;
yeah[x].push_back(sb);
}
if(l == r) {
return;
}
long long m = (l+r)/2;
build(l,m,x*2);
build(m+1,r,x*2+1);
}
void calc(long long l, long long r, long long x, long long ql, long long qr) {
if(l == ql && r == qr) {
if(sm < 0) {
return;
}
long long bl = 0,br = bruh[x].size()-1;
ans+=wow[x];
if(sm >= bruh[x][1]) {
sm = bruh[x][bruh[x].size()-1];
return;
}
long long c = (bruh[x][1]-sm+d-1)/d;
while(bl < br) {
long long mid = (bl+br+1)/2;
if(yay[x][mid] <= c) {
bl = mid;
}
else {
br = mid-1;
}
}
ans+=c*bl-yeah[x][bl];
sm = min(sm,bruh[x][bruh[x].size()-1]-d*(max(0LL,c-yay[x][bruh[x].size()-1])));
return;
}
long long m = (l+r)/2;
if(qr <= m) {
calc(l,m,x*2,ql,qr);
}
else if(ql > m) {
calc(m+1,r,x*2+1,ql,qr);
}
else {
calc(m+1,r,x*2+1,m+1,qr);
calc(l,m,x*2,ql,m);
}
}
int main()
{
ios_base::sync_with_stdio(false);
cin.tie(NULL);
cout.tie(NULL);
long long n,q,l,r;
cin >> n >> d;
for(long long i = 1; i <= n; i++) {
cin >> haha[i];
}
cin >> q;
build(1,n,1);
for(long long i = 0; i < q; i++) {
ans = 0;
sm = LLONG_MAX;
cin >> l >> r;
calc(1,n,1,l,r);
if(sm < 0) {
cout << -1 << "\n";
}
else {
cout << ans << "\n";
}
}
return 0;
}
