#include <bits/stdc++.h>
//qwerty47924692
using namespace std;
using ll = long long;
const ll N=5e5+29;
const string br="617283";
#define sz(a)(ll)a.size()
#define f first
#define s second
ll n,q,w[N],st[4*N],z[4*N],lg[N],l[N],r[N],ans[N];
vector<ll>v[N];
vector<pair<ll,ll>>g[N];
ll mx[N][20];
void build(){
lg[1]=0;
for(ll i=2;i<=n;i++)lg[i]=lg[i/2]+1;
for(ll j=1;j<20;j++){
ll k=(1ll<<j);
for(ll i=k-1;i<=n;i++){
mx[i][j]=max(mx[i][j-1],mx[i-k/2][j-1]);
}
}
}
ll get(ll l,ll r){
ll k=lg[r-l+1];
return max(mx[r][k],mx[l+(1ll<<k)-1][k]);
}
void push(ll v,ll l,ll r){
if(!z[v])return;
ll mid=(r+l)>>1;
st[v*2]=max(st[v*2],z[v]+get(l,mid));
st[v*2+1]=max(st[v*2+1],z[v]+get(mid+1,r));
z[v*2]=max(z[v*2],z[v]);
z[v*2+1]=max(z[v*2+1],z[v]);
z[v]=0;
}void upd(ll v,ll l,ll r,ll x,ll y,ll val){
if(l>y||x>r)return;
if(x<=l&&r<=y){
st[v]=max(st[v],val+get(l,r));
z[v]=max(z[v],val);
return;
}
push(v,l,r);
ll mid=(r+l)>>1;
upd(v*2,l,mid,x,y,val);
upd(v*2+1,mid+1,r,x,y,val);
st[v]=max(st[v*2],st[v*2+1]);
}ll get(ll v,ll l,ll r,ll x,ll y){
if(l>y||x>r)return 0;
if(x<=l&&r<=y)return st[v];
ll mid=(r+l)>>1;
push(v,l,r);
return max(get(v*2,l,mid,x,y),get(v*2+1,mid+1,r,x,y));
}
ll s[N],sz=0;
int main(){
ios_base::sync_with_stdio(0);
cin.tie(0);
cin>>n;
for(ll i=1;i<=n;i++){
cin>>w[i];
mx[i][0]=w[i];
}ll q;
cin>>q;
for(ll i=1;i<=n;i++){
while(sz&&w[s[sz]]<=w[i]){
sz--;
}
l[i]=s[sz];
s[++sz]=i;
}
sz=0;
s[sz]=n+1;
for(ll i=n;i>=1;i--){
while(sz&&w[s[sz]]<w[i]){
sz--;
}
r[i]=s[sz];
s[++sz]=i;
}sz=0;
build();
for(ll i=1;i<=n;i++){
v[i].push_back(r[i]);
v[l[i]].push_back(i);
}
for(ll i=1;i<=q;i++){
ll L,R,ans=0;
cin>>L>>R;
g[L].push_back({R,i});
}for(ll i=n;i>=1;i--){
for(auto j:v[i]){
upd(1,1,n,2*j-i,n,w[i]+w[j]);
}for(auto [r,id]:g[i]){
ans[id]=get(1,1,n,i,r);
}
}
for(ll i=1;i<=q;i++){
cout<<ans[i]<<'\n';
}
}
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