#pragma GCC optimize("Ofast")
#pragma GCC optimize("unroll-loops")

#include <bits/stdc++.h>

using namespace std;
using ll = long long;

const ll mod = 1e9 + 7;
const ll mod2 = 998244353;

ll gcd(ll a, ll b) {
    return b ? gcd(b, a % b) : a;
}

ll pow(ll a, ll b) {
    ll ans = 1;
    while (b) {
        if (b & 1) ans *= a;
        b >>= 1;
        a *= a;
    }
    return ans;
}

ll pow(ll a, ll b, ll c) {
    ll ans = 1;
    while (b) {
        if (b & 1) ans = (ans * a) % c;
        b >>= 1;
        a = (a * a) % c;
    }
    return ans;
}

void check(bool b) {
    if (b)
        cout << "Yes\n";
    else
        cout << "No\n";
}

int main() {
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);
    cout.tie(nullptr);
    int t = 1;
//    cin >> t;
    while (t--) {
        ll n;cin>>n;
        vector<ll>a(n);
        for (int i = 0; i < n; ++i) {
            cin>>a[i];
        }
        ll last=0;
        vector<ll>v(n);
        vector<ll>v1(n);
        v[0]=a[0];
        for (int i = 1; i < n; ++i) {
            if (a[i]==0 ||a[i-1]==0)
                last=i;
            v[last]+=a[i];
            v1[i]=last;
        }
        ll q;cin>>q;
        while (q--){
            ll p,x;cin>>p>>x;
            --p;
            if (a[p]){
                cout<<v[v1[p]]+x-a[p]<<'\n';
            } else{
                if (p)x+=v[v1[p-1]];
                if (p<n-1)x+=v[v1[p+1]];
                cout<<x<<'\n';
            }
        }
    }
    return 0;
}