#include<bits/stdc++.h>
namespace {
#pragma GCC diagnostic ignored "-Wunused-function"
#include<atcoder/all>
#pragma GCC diagnostic warning "-Wunused-function"
using namespace std;
using namespace atcoder;
#define rep(i,n) for(int i = 0; i < (int)(n); i++)
#define rrep(i,n) for(int i = (int)(n) - 1; i >= 0; i--)
#define all(x) begin(x), end(x)
#define rall(x) rbegin(x), rend(x)
template<class T> bool chmax(T& a, const T& b) { if (a < b) { a = b; return true; } else return false; }
template<class T> bool chmin(T& a, const T& b) { if (b < a) { a = b; return true; } else return false; }
using ll = long long;
using P = pair<int,int>;
using VI = vector<int>;
using VVI = vector<VI>;
using VL = vector<ll>;
using VVL = vector<VL>;

} int main() {
  ios::sync_with_stdio(false);
  cin.tie(0);
  int n;
  cin >> n;
  VI a0(n + 2);
  VL a(n + 2);
  rep(i, n) cin >> a[i + 1], a0[i+1] = a[i+1];
  n += 2;
  dsu uf(n);
  rep(i, n - 1) if (a[i] && a[i+1]) {
    int l1 = uf.leader(i), l2 = uf.leader(i + 1);
    a[uf.merge(l1, l2)] = a[l1] + a[l2];
  }
  int q;
  cin >> q;
  while (q--) {
    int x, b;
    cin >> x >> b;
    ll ans = 0;
    if (a[x] == 0) {
      ans = a[uf.leader(x - 1)] + a[uf.leader(x + 1)] + b;
    } else {
      ans = a[uf.leader(x)] + b - a0[x];
    }
    cout << ans << '\n';
  }
}