#include <bits/stdc++.h>

using namespace std;

#ifdef LOCAL
#include "debug.h"
#else
#define dbg(...)
#endif


template<class T>
struct SegTree {
	const T INIT{};
	int size; vector<T> seg;
	SegTree(int n, vector<T>&v) : size(1){
		while(size < n) size <<= 1;
		seg.assign(2*size+1, INIT); build(v);
	}
	T cmb(T a, T b){ 
		return a + b;
	}
	void build(vector<T>&a) { build(a, 0, 0, size); }
	void pull(T p){ seg[p] = cmb(seg[2*p+1], seg[2*p+2]); }
	void upd(int i, int v) { upd(i, v, 0, 0, size); }
	T query(int l, int r) { return query(l, r, 0, 0, size); }
	
	void build(vector<T>&a, int node, int left, int right){
		if (left == right){ if (left < a.size()) { seg[node] = a[left]; } return;}
		int mid = left + (right - left) / 2;
		build(a, node*2+1, left, mid); build(a, node*2+2, mid+1, right);
		pull(node);
	}
	void upd(int i, int v, int node, int left, int right) {
		if (left == right){ seg[node] = v; return; }
		int mid = left + (right - left) / 2;
		if (i <= mid){ upd(i,v,node*2+1, left, mid); }
		else { upd(i,v,node*2+2, mid+1, right); }
		pull(node);
	}
	T query(int l, int r, int node, int left, int right){
		if (l > right || r < left) return INIT;
		if (left >= l && right <= r) return seg[node];
		int mid = left + (right - left) / 2;
		return cmb(query(l, r, node*2+1, left, mid), query(l, r, node*2+2, mid+1, right));
	}
};

void solve(){
	//20 70 40 10 50
	//20 90 130 140 190
	int n;
	cin >> n;
	vector<int>v(n-1);
	for (auto &a : v){
		cin >> a;
	}
	SegTree st(n, v);
	int q;
	cin >> q;
	int mn = 1e9;
	auto bst = [&](){
		int l = 0, r = n-1;
		while(l < r){
			int m = l + (r - l) / 2;
			mn = min(mn, abs(st.query(0, m) - st.query(m+1, n-1)));
			// dbg(m, st.query(0,m), st.query(m+1, n-1));
			if (st.query(0, m) > st.query(m+1, n-1)){
				r = m;
			}
			else {
				l = m+1;
			}
		}
	};
	bst();
	cout << mn << endl;
	while(q--){
		mn = 1e9;
		int x,val;
		cin >> x >> val;
		st.upd(x-1, val);
		bst();
		cout << mn << endl;
	}
	
}


int main(){
	ios::sync_with_stdio(false);
	cin.tie(0);

    int tc = 1;
    // cin >> tc;
    for (int i = 1; i <= tc; i++){
        //cout << "Case #" << i << ": ";
        solve();
    }
    
    return 0;
}

answer.code: In function ‘void solve()’:
answer.code:58:17: error: missing template arguments before ‘st’
   58 |         SegTree st(n, v);
      |                 ^~
answer.code: In lambda function:
answer.code:66:42: error: ‘st’ was not declared in this scope; did you mean ‘bst’?
   66 |                         mn = min(mn, abs(st.query(0, m) - st.query(m+1, n-1)));
      |                                          ^~
      |                                          bst
answer.code: In function ‘void solve()’:
answer.code:82:17: error: ‘st’ was not declared in this scope; did you mean ‘bst’?
   82 |                 st.upd(x-1, val);
      |                 ^~
      |                 bst