#include <bits/stdc++.h>
// #include <ext/pb_ds/assoc_container.hpp>
// #include <ext/pb_ds/tree_policy.hpp>
#define INF 1e9
#define INFl 1e18
#define all(x) x.begin(), x.end()
#define sajz(x) (int)x.size()
#define pb push_back
#define s second
#define f first
#define yes puts("YES")
#define no puts("NO")
#define erase_duplicates(x) {sort(all(x));(x).resize(distance((x).begin(), unique(all(x))));}
using namespace std;
//using namespace __gnu_pbds;
void __print(int x) {cerr << x;}
void __print(long x) {cerr << x;}
void __print(long long x) {cerr << x;}
void __print(unsigned x) {cerr << x;}
void __print(unsigned long x) {cerr << x;}
void __print(unsigned long long x) {cerr << x;}
void __print(float x) {cerr << x;}
void __print(double x) {cerr << x;}
void __print(long double x) {cerr << x;}
void __print(char x) {cerr << '\'' << x << '\'';}
void __print(const char *x) {cerr << '\"' << x << '\"';}
void __print(const string &x) {cerr << '\"' << x << '\"';}
void __print(bool x) {cerr << (x ? "true" : "false");}

template<typename T, typename V>
void __print(const pair<T, V> &x) {cerr << '{'; __print(x.first); cerr << ','; __print(x.second); cerr << '}';}
template<typename T>
void __print(const T &x) {int f = 0; cerr << '{'; for (auto &i: x) cerr << (f++ ? "," : ""), __print(i); cerr << "}";}
void _print() {cerr << "]\n";}
template <typename T, typename... V>
void _print(T t, V... v) {__print(t); if (sizeof...(v)) cerr << ", "; _print(v...);}
#ifndef ONLINE_JUDGE
#define debug(x...) cerr << "[" << #x << "] = ["; _print(x)
#else
#define debug(x...)
#endif

#define int ll

typedef long long ll;
typedef unsigned long long ull;
typedef pair<int,int> pii;
typedef vector<int> vi;
typedef vector<ll> vll;
typedef set<int> si;
typedef multiset<int> msi;
typedef long double ld;
//typedef cc_hash_table<int, int, hash<int>> ht;
const int base = (1 << 20);
vi t(2*base, 0);
void modify(int idx, int val) {
	int cur = base+idx;
	int prev = t[cur];
	while(cur > 0) {
		t[cur] += val-prev;
		cur /= 2;
	}
}
int query(int node, int ns, int ne, int qs, int qe) {
	if(ne < qs || qe < ns) return 0;
	if(qs <= ns && ne <= qe) return t[node];

	int mid = (ns+ne)/2;
	int left = query(2*node, ns, mid, qs, qe);
	int right = query(2*node+1, mid+1, ne, qs, qe);
	return left+right;
}
void test_case() {
	int n;
	cin >> n;
	vi v(n);
	for(int i = 1; i < n; i++) {
		cin >> v[i];
		modify(i, v[i]);
	}
	function<int(void)> ans = [&]() {
		int l = -1, r = n+1;
		int res = 1e15;
		while(r-l>1) {
			int mid = l+(r-l)/2;
			int x = query(1, 0, base-1, 0, mid);
			int y = t[1]-x;
			// debug(mid, x, y);
			res = min(res, abs(x-y));
			if(x > y) r = mid;
			else l = mid;
		}
		return res;
	};
	cout << ans() << "\n";
	int k;
	cin >> k;
	for(int i = 0; i < k; i++) {
		int idx, val;
		cin >> idx >> val;
		modify(idx, val);
		cout << ans() << "\n";
	}
}

int32_t main() {
	ios_base::sync_with_stdio(false);
	cout.tie(0);
	cin.tie(0);

	int tc=1;
	//cin >> tc;
	while(tc--)test_case();

	return 0;
}