#include <bits/stdc++.h>
#ifdef ONLINE_JUDGE
#define freopen(...) 0
#endif
#define V vector
#define fi first
#define se second
#define ins emplace
#define eb emplace_back
#define FO(i, a, b) F(i, a, (b) - 1)
#define RO(i, a, b) R(i, a, (b) - 1)
#define F(i, a, b) for (int i = (a), iee = (b); i <= iee; i++)
#define R(i, a, b) for (int i = (b), iee = (a); i >= iee; i--)
#define rsz resize
#define sz(x) (x).size()
using namespace std;
using str = string;
using ll = long long;
using u32 = unsigned;
using db = long double;
using i128 = __int128_t;
using u128 = __uint128_t;
using u64 = decltype(1ull);
template <typename T, typename U = less<>>
using pq = priority_queue<T, V<T>, U>;
mt19937_64 rng(chrono::steady_clock::now().time_since_epoch().count());
ll rand(ll l, ll r) { return rng() % (r - l + 1) + l; }

const int N = 200100;
int n, q, c[N];
ll a[N], b[N];

#define lc p << 1
#define rc lc | 1
#define mid ((l + r) >> 1)
ll mx[N << 2], tag[N << 2];
void push(int p, ll k) { mx[p] += k, tag[p] += k; }
void up(int p) { mx[p] = max(mx[lc], mx[rc]); }
void down(int p) { push(lc, tag[p]), push(rc, tag[p]), tag[p] = 0; }
void modify(int x, int y, ll k, int l, int r, int p) {
	if (x > r || y < l) return;
	if (x <= l && y >= r) return push(p, k);
	down(p), modify(x, y, k, l, mid, lc), modify(x, y, k, mid + 1, r, rc), up(p);
}
void build(int l, int r, int p) {
	tag[p] = 0;
	if (l == r) { mx[p] = a[r] - b[r]; return; }
	build(l, mid, lc), build(mid + 1, r, rc), up(p);
}

int main() {
	freopen("QOJ6630.in", "r", stdin),
	freopen("QOJ6630.out", "w", stdout),
	cin.tie(0)->sync_with_stdio(0);
	cin >> n >> q;
	F(i, 1, n) cin >> c[i];
	ll sum = 0;
	F(i, 1, n) a[i] += c[i] >> 1, b[(i + 1) >> 1] += c[i] & 1;
	F(i, 1, n) a[i] += a[i - 1], b[i] += b[i - 1];
	build(1, n, 1);
	sum = a[n];

	F(i, 1, q) {
		int p, d;
		cin >> p >> d;
		int q = (p + 1) >> 1;
		ll da = 0, db = 0;
		da -= c[p] >> 1, db -= c[p] & 1;
		c[p] += d;
		da += c[p] >> 1, db += c[p] & 1;
		sum += da;
		modify(p, n, da, 1, n, 1);
		modify(q, n, -db, 1, n, 1);
		cout << sum - (max(0ll, mx[1]) + 2) / 3 << "\n";
	}
}