#include<bits/stdc++.h>
using namespace std;
using ll = long long;
int n , q , one , two , uno , aage , stcksiz;
long long d , c[300001] , pre[300001] , presum[300001] , tot[300001] , vag[300001] , ans[300001] , ek , dui , tin;
long long stckans[300001];
deque<pair<long long , int>> stck; // f9irst val second index
struct QQ{
int first;
int second;
long long third;
};
bool comp( QQ me , QQ him ) {
return me.first < him.first;
}
vector<QQ> qq;
int getans( int me ) {
int l = 1;
int r = (int)stck.size() - 1;
while( l < r ) {
int m = (l + r) / 2;
if( stck[m].second >= me ) r = m;
else l = m + 1;
}
return l;
}
int main() {
cin >> n >> d;
for( int z = 1; z <= n; z++ ) {
cin >> c[z];
vag[z] = c[z] % d;
tot[z] = (c[z] - (c[z] % d)) / d;
tot[z] = tot[z] + tot[z - 1];
if( vag[z] < vag[z - 1] ) pre[z] = 1;
pre[z] += pre[z - 1]; // pre is the count before this
presum[z] = pre[z] + presum[z - 1];
}
cin >> q;
for( int z = 1; z <= q; z++ ) {
cin >> one >> two;
qq.push_back({two , one , z });
}
qq.push_back({0 , 0 , 0});
sort(qq.begin() , qq.end() , comp );
stck.push_back({(ll)(-2000000000000 ) , 0 });
for( int z = 1; z <= q; z++ ) {
if( qq[z].first > qq[z - 1].first ) {
for( int y = qq[z - 1].first + 1; y <= qq[z].first; y++ ) {
ek = ( tot[y] - tot[y - 1] ) - pre[y];
stcksiz = (int)stck.size();
while( stcksiz > 1 && stck.back().first >= ek ) {
stck.pop_back();
stcksiz--;
stckans[stcksiz] = 0;
}
one = stck.back().second;
tin = stck.back().first;
stck.push_back({ek , y});
stckans[stcksiz] = (ll)(y - one)*(ek); // was ek - tin
stckans[stcksiz] += stckans[stcksiz - 1];
}
}
one = qq[z].second;
two = getans(one);
tin = stckans[(int)stck.size() - 1] - stckans[two];
tin += stck[two].first * ( (ll)(stck[two].second - one + 1) );
//cout << tin << "\n";
dui = stck[two].first + pre[one]; // kotote thakar kotha
if( dui < 0 ) ans[qq[z].third] = -1;
else{
// cout << dui << "\n";
tin += ((dui - stck[two].first) * (ll)(qq[z].first - qq[z].second + 1));
//cout << tin << "\n";
tin += ( presum[qq[z].first] - presum[qq[z].second] ) -
(pre[qq[z].second] * (ll)(qq[z].first - qq[z].second) );
// cout << tin << "\n";
tin = (tot[qq[z].first] - tot[qq[z].second - 1]) - tin;
ans[qq[z].third] = tin;
}
}
// for( int z = 0; z < (int)stck.size(); z++ ) {
//cout << stck[z].first << " " << stck[z].second << " " << stckans[z] << "\n";
// }
for( int z = 1; z <= q; z++ ) cout << ans[z] << "\n";
return 0;
}
