Submission #2194065

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Source Code Expand

#include <bits/stdc++.h>

#define _overload(_1,_2,_3,name,...) name
#define _rep(i,n) _range(i,0,n)
#define _range(i,a,b) for(int i=int(a);i<int(b);++i)
#define rep(...) _overload(__VA_ARGS__,_range,_rep,)(__VA_ARGS__)

#define _rrep(i,n) _rrange(i,n,0)
#define _rrange(i,a,b) for(int i=int(a)-1;i>=int(b);--i)
#define rrep(...) _overload(__VA_ARGS__,_rrange,_rrep,)(__VA_ARGS__)

#define _all(arg) begin(arg),end(arg)
#define uniq(arg) sort(_all(arg)),(arg).erase(unique(_all(arg)),end(arg))
#define getidx(ary,key) lower_bound(_all(ary),key)-begin(ary)
#define clr(a,b) memset((a),(b),sizeof(a))
#define bit(n) (1LL<<(n))
#define popcount(n) (__builtin_popcountll(n))

using namespace std;

template<class T>bool chmax(T &a, const T &b) { return (a < b) ? (a = b, 1) : 0;}
template<class T>bool chmin(T &a, const T &b) { return (b < a) ? (a = b, 1) : 0;}

using ll = long long;
using R = long double;
const R EPS = 1e-9L; // [-1000,1000]->EPS=1e-8 [-10000,10000]->EPS=1e-7
inline int sgn(const R& r) {return (r > EPS) - (r < -EPS);}
inline R sq(R x) {return sqrt(max(x, 0.0L));}

const int dx[8] = {1, 0, -1, 0, 1, -1, -1, 1};
const int dy[8] = {0, 1, 0, -1, 1, 1, -1, -1};

// Problem Specific Parameter:

const int limit = 200010;
ll a[limit], b[limit];
const ll inf = 1LL << 60;


multiset<ll> positive, negative;
ll a_total = 0LL, p_total = 0LL;

int n, q;

inline void add(int i) {
	a_total += a[i];
	if (i == 0 or i == 2 * n - 1) return;
	const ll val = b[i] - a[i];
	if (val >= 0) {
		positive.insert(val);
		p_total += val;
	} else {
		negative.insert(val);
	}
}

inline void del(int i) {
	a_total -= a[i];
	if (i == 0 or i == 2 * n - 1) return;
	const ll val = b[i] - a[i];
	if (val >= 0) {
		auto it = positive.find(val);
		positive.erase(it);
		p_total -= val;
	} else {
		auto it = negative.find(val);
		negative.erase(it);
	}
}

int main(void) {
	cin >> n >> q;

	rep(i, 2 * n) cin >> a[i];
	rep(i, 2 * n) cin >> b[i];

	rep(i, 2 * n) a_total += a[i];

	rep(i, 1, 2 * n - 1) {
		const ll val = b[i] - a[i];
		if (val >= 0) {
			positive.insert(val);
			p_total += val;
		} else {
			negative.insert(val);
		}
	}


	rep(loop, q) {
		int p;
		ll x, y;
		cin >> p >> x >> y;

		del(p - 1);
		a[p - 1] = x, b[p - 1] = y;
		add(p - 1);

		ll ans = -inf;
		if (positive.size() % 2 == 0) {
			chmax(ans, a_total + p_total);
		} else {
			const ll mmax = *prev(end(negative));
			const ll pmin = *begin(positive);
			chmax(ans, a_total + p_total + mmax);
			chmax(ans, a_total + p_total - pmin);
		}

		cout << ans << endl;
	}

	return 0;
}

Submission Info

Judge Result