#include<bits/stdc++.h>
//#include <atcoder/all>
using namespace std;
//using namespace atcoder;

#define all(v) v.begin(),v.end()
using ll = long long;
using ull = unsigned long long;
using lll = __int128;
using vll=vector<ll>;
using vvll = vector<vector<ll>>;
using P = pair<ll,ll>;
using vp=vector<pair<ll, ll>>;
//using mint=modint1000000007;
//using mint=modint998244353;

const ll INF=1ll<<60;
ll mod10=1e9+7;
ll mod99=998244353;
const double PI = acos(-1);

#define rep(i,n) for (ll i=0;i<n;++i)
#define per(i,n) for(ll i=n-1;i>=0;--i)
#define rep2(i,a,n) for (ll i=a;i<n;++i)
#define per2(i,a,n) for (ll i=a;i>=n;--i)

template<class T>bool chmax(T &a, const T &b) { if (a<b) { a=b; return true; } return false; }
template<class T>bool chmin(T &a, const T &b) { if (b<a) { a=b; return true; } return false; }

struct unionfind{
    ll N;
    vector<ll> par,Rank,Size;
    unionfind(ll n):N(n){
        par=vector<ll>(N),Rank=vector<ll>(N,1),Size=vector<ll>(N,1);
        for(int i=0;i<N;i++) par[i]=i;
    };
    ll find(ll x){
        if(par[x]==x) return x;
        else return par[x]=find(par[x]);
    }

    bool same(ll a,ll b){
        return find(a)==find(b);
    }

    void unite(ll a,ll b){
        if(same(a,b))return;
        a=find(a);
        b=find(b);
        ll s=Size[a]+Size[b];
        if(Rank[b]>Rank[a]) par[a]=b;
        else par[b]=a;
        if(Rank[a]==Rank[b]) Rank[a]++;
        Size[find(a)]=s;
    }

    ll size(ll a){
       return Size[find(a)];
    }
};

bool solve(){
    ll N;cin>>N;
    vll A(N);rep(i,N) cin>>A[i];
    unionfind uf(N);
    rep(i,N){
        if(A[i]){
            if(i>0&&A[i-1]>0) uf.unite(i,i-1);
            if(i<N-1&&A[i+1]>0) uf.unite(i,i+1);
        }
    }
    vll sum(N);rep(i,N) sum[uf.find(i)]+=A[i];
    ll Q;cin>>Q;
    rep(i,Q){
        ll j,x;cin>>j>>x;
        j--;
        ll ans=0;
        if(uf.size(j)==1){
            if(j>0) ans+=sum[uf.find(j-1)];
            if(j<N-1) ans+=sum[uf.find(j+1)];
            ans+=x;
        }else{
            ans+=sum[uf.find(j)]-A[j]+x;
        }
        cout<<ans<<endl;
    }
    return 0;
}



int main(){
    cin.tie(0);
    ios::sync_with_stdio(false);
    ll T=1;//cin>>T;
    rep(i,T) solve();
}