#include <bits/stdc++.h>
#define pb push_back
#define ppb pop_back
#define pf push_front
#define ppf pop_front
#define ll long long
#define zeros(x) ( (x ^ (x - 1)) & x )
using namespace std;
unsigned seed = chrono::system_clock::now().time_since_epoch().count();
mt19937 rng(seed);
#define rand() rng()
/*const long long mod = 998244353;
long long fct[200005],invfct[200005],inv[200005];
long long put2[200005];
long long lgput (long long a, long long exp)
{
long long rz=1;
while(exp)
if(exp&1)
exp^=1,rz=rz*1LL*a%mod;
else
exp>>=1,a=a*1LL*a%mod;
return rz;
}
long long cmb (long long n, long long k)
{
if(n<k || k<0 || n<0)
return 0;
return fct[n]*1LL*invfct[k]%mod*1LL*invfct[n-k]%mod;
}
void init ()
{
inv[1]=fct[0]=fct[1]=invfct[0]=invfct[1]=put2[0]=1,put2[1]=2;
for(long long i=2;i<=200000;++i)
put2[i]=put2[i-1]*2LL%mod,inv[i]=(mod-mod/i)*1LL*inv[mod%i]%mod,fct[i]=i*1LL*fct[i-1]%mod,invfct[i]=inv[i]*1LL*invfct[i-1]%mod;
}
long long v[200005];*/
const ll N=2e5+5;
ll n,v[5005],nxt[5005],dp[5005];
void solve()
{
cin>>n;
for(ll i=1;i<=n;i++)
cin>>v[i];
for(ll i=1;i<=n;i++)
{
ll sum=0;
nxt[i]=0;
for(ll j=i;j<=n;j++)
{
sum+=v[j];
if(sum==0)
{
nxt[i]=j;
break;
}
}
}
ll q;
cin>>q;
while(q--)
{
ll l,r;
cin>>l>>r;
dp[r]=(v[r]==0);
for(int i=r-1;i>=l;i--)
{
dp[i]=dp[i+1];
if(v[i]==0)
dp[i]++;
else
{
if(nxt[i]<=r && nxt[i]>0)
dp[i]=max(dp[i],dp[nxt[i]]+1);
}
}
cout<<dp[l]<<"\n";
}
}
int main()
{
ios_base::sync_with_stdio(false);
cin.tie(NULL);
ll t=1;
//cin>>t;
while(t--)
solve();
return 0;
}
