记录编号	618327	评测结果	AAAAAAAAAA
题目名称	4465.无法拒绝孤独的她	最终得分	100
用户昵称	RpUtl	是否通过	通过
代码语言	C++	运行时间	4.103 s
提交时间	2026-08-28 20:33:24	内存使用	29.96 MiB

#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
const int N = 5e5 + 10;
const ll inf = 1e18 + 10;
ll a[N], b[N], c[N];
struct Data {
	int l, r;
	ll flow, nowto, rest, restto; 
	void init(int x) {
		l = r = x;
		flow = min(b[x], a[x]);
		nowto = max(0ll, a[x] - b[x]);
		rest = max(0ll, b[x] - a[x]);
		restto = inf;
	}
} w;
ll can, incf, incto, ncan, nvrest;
Data operator + (const Data &u, const Data &v) {
	w.l = u.l, w.r = v.r; 
	can = min(c[u.r], u.nowto), incf = min(can, v.rest);
	incto = min(v.restto, max(can - v.rest, 0ll));
	w.flow = u.flow + v.flow + incf, w.nowto = v.nowto + incto;
	w.rest = u.rest + min({u.restto, c[u.r] - can, v.rest - incf});
	ncan = min(u.restto, c[u.r] - can), nvrest = v.rest - incf;
	w.restto = min(v.restto - incto, max(ncan - nvrest, 0ll)); 
	return w;
}
struct sgt {
	Data val[N << 2];
	#define ls (p << 1)
	#define rs (p << 1 | 1)
	void pushup(int p) {
		val[p] = val[ls] + val[rs];
	}
	void upd(int p, int l, int r, int x) {
		if (l == r) {
			val[p].init(x);
		} else {
			int mid = (l + r) >> 1;
			if (x <= mid) upd(ls, l, mid, x);
			if (x > mid) upd(rs, mid + 1, r, x);
			pushup(p);
		}
	}
	void build(int p, int l, int r) {
		if (l == r) {
			val[p].init(l);
		} else {
			int mid = (l + r) >> 1;
			build(ls, l, mid);
			build(rs, mid + 1, r);
			pushup(p);
		}
	}
} T;
int n, q;
int main() {
	freopen("cantrefuse.in", "r", stdin);
	freopen("cantrefuse.out", "w", stdout);
	ios::sync_with_stdio(0);
	cin.tie(0), cout.tie(0);
	cin >> n >> q;
	for (int i = 1; i <= n; i++) cin >> a[i];
	for (int i = 1; i <= n; i++) cin >> b[i];
	for (int i = 1; i < n; i++) cin >> c[i];
	T.build(1, 1, n); 
	ll p, x, y, z;
	while (q--) {
		cin >> p >> x >> y >> z;
		a[p] = x, b[p] = y, c[p] = z;
		T.upd(1, 1, n, p);
		cout << T.val[1].flow << '\n';
	}
	return 0;
}