#include<stdio.h>
#include<stdlib.h>
#define N 300000
#define Q 300000
int n, q, *eh[N+1], eo[N+1];
long long d,ans[Q];
void push(int i,int j)
{
int o=eo[i]++;
if(!o)eh[i]=(int*)malloc(2*sizeof**eh);
else if(!(o&o-1))eh[i]=(int*)realloc(eh[i],2*o*sizeof**eh);
eh[i][o]=j;
}
/*
* sweep from left to right,
*
* decompose fishes to dominoes
*
* amortized O(n) dominoes move
*
*
* need segtree that can
* decrease k from a[l..r], add k to b[l..r]
* point query a[i]
* range query b[l..r]
*/
#define N_ (((N+1)<<2)+1)
long long ta[N_], la[N_], tb[N_], lb[N_], c;
int dominoes[N+1], top;
void pul(int v,int l,int r)
{
long long m=l+(r-l)/2, w1=m-l+1, w2=r-m;
ta[v] = ta[2*v] + ta[2*v+1] + w1 * la[2*v] + w2 * la[2*v+1];
tb[v] = tb[2*v] + tb[2*v+1] + w1 * lb[2*v] + w2 * lb[2*v+1];
}
void add(int x,int y,long long k,long long k2,int v,int l,int r)
{
if (r < x || y < l) return;
if (x <= l && r <= y)
{
la[v] += k;
lb[v] += k2;
return;
}
add(x, y, k, k2, 2*v, l, l+(r-l)/2);
add(x, y, k, k2, 2*v+1, l+(r-l)/2+1, r);
pul(v, l, r);
}
void add_(int x,int y,long long k,long long k2) { add(x, y, k, k2, 1, 0, n); }
long long query1(int p,int v,int l,int r)
{
if(l==r)return ta[v] + la[v];
return la[v] + (p <= l+(r-l)/2 ? query1(p,2*v,l,l+(r-l)/2): query1(p,2*v+1,l+(r-l)/2+1,r));
}
long long query1_(int p) { return query1(p, 1, 0, n); }
int max(int i,int j){return i>j?i:j;}
int min(int i,int j){return i<j?i:j;}
int overlap(int x,int y,int a, int b) { return(y<a||b<x)? 0:min(b,y)-max(x,a)+1; }
long long query2(int x,int y,int v,int l,int r)
{
if(r<x||y<l)return 0;
if (x<=l&&r<=y) return lb[v] * (r-l+1ll) + tb[v];
return lb[v] * overlap(x,y,l,r) + query2(x, y, 2*v, l, l+(r-l)/2) + query2(x, y, 2*v+1, l+(r-l)/2+1, r);
}
long long query2_(int x,int y) { return query2(x, y, 1, 0, n); }
int broken = 0;
void fix(int r)
{
long long delta = query1_(r-1) - query1_(r);
if (delta <= 0)
return;
long long ii = (delta + d - 1) / d;
if (query1_(dominoes[top]) < d * ii)
{
int lower = dominoes[top], upper = r;
while (upper - lower > 1)
{
int mid = lower + (upper - lower) / 2;
if (query1_(mid) < d * ii) lower = mid;
else upper = mid;
}
if (lower > broken)
{
broken = lower;
add_(broken, broken, -1e18, 0);
dominoes[top=1]=broken+1;
}
}
add_(dominoes[top], r-1, -ii * d, ii);
}
int main()
{
scanf("%d%lld",&n,&d);
add_(0, 0, -1e18, 0);
for(int i=1;i<=n;++i)scanf("%lld",&c), add_(i, i, c, 0);
scanf("%d",&q);
for(int ll,rr,i=0;i<q;++i)scanf("%d%d",&ll,&rr),push(rr,i),push(rr,ll);
for(int r=1;r<=n;++r)
{
fix(r);
while (top && query1_(dominoes[top]) - query1_(dominoes[top]-1) < d)
fix(dominoes[top--]);
if (query1_(r) - query1_(r-1) >= d)
dominoes[++top] = r;
for(int j=0;j<eo[r];j+=2)
{
int ll=eh[r][j+1], ii=eh[r][j];
ans[ii] = (broken >= ll) ? -1 : query2_(ll, r);
}
}
for(int i=0;i<q;++i)printf("%lld\n",ans[i]);
}
