Submission #1065500

#	Time	Username	Problem	Language	Result	Execution time	Memory
1065500		Tob	Arranging Tickets (JOI17_arranging_tickets)	C++14	100 / 100	1522 ms	20920 KiB

arranging_tickets

#include <bits/stdc++.h>

#define F first
#define S second
#define all(x) x.begin(), x.end()
#define pb push_back
#define FIO ios_base::sync_with_stdio(false); cin.tie(0); cout.tie(0)

using namespace std;

typedef long long ll;
typedef pair <ll, ll> pii;

const int N = 2e5 + 7;

int n, m;
ll a[N], l[N], r[N], c[N], ps[N];
vector <pii> iv[N];
map <ll, ll> s;

bool check(int t, ll b, ll d) {
	if (d > b || d < 0) return 0;
	s.clear();
	for (int i = 0; i <= n; i++) ps[i] = 0;
	ll cnt = 0;
	for (int i = 1; i <= t; i++) {
		ll ne = (a[i]-b+d+1)/2;
		for (auto it : iv[i]) if (it.F >= t) s[it.F] += it.S;
		while (cnt < ne) {
			if (s.empty()) return 0;
			auto p = --s.end();
			ll dod = ne-cnt;
			if (p->S <= ne-cnt) {
				dod = p->S;
				s.erase(p);
			}
			else s[p->F] -= dod;
			cnt += dod;
			ps[0] += dod;
			ps[i] -= 2*dod;
			ps[p->F+1] += 2*dod;
		}
	}
	for (int i = 0; i < n; i++) {
		if (i) ps[i] += ps[i-1];
		if (a[i] + ps[i] > b) return 0;
	}
	return 1;
}

int main () {
	FIO;
	cin >> n >> m;
	
	for (int i = 0; i < m; i++) {
		cin >> l[i] >> r[i] >> c[i];
		if (l[i] > r[i]) swap(l[i], r[i]);
		r[i]--;
		a[l[i]] += c[i];
		a[r[i]+1] -= c[i];
		iv[l[i]].pb({r[i], c[i]});
	}
	for (int i = 1; i < n; i++) a[i] += a[i-1];
	int p = 1;
	for (int i = 2; i < n; i++) if (a[i] > a[p]) p = i;
	
	ll lo = 0, hi = a[p];
	while (lo < hi) {
		ll mid = (lo + hi) / 2;
		int o = 0;
		o |= check(p, mid, a[p]-mid) | check(p, mid, a[p]-mid+1);
		if (o) hi = mid;
		else lo = mid+1;
	}
	cout << lo << "\n";

	return 0;
}

• Subtask 1: 10 / 10
• Subtask 2: 35 / 35
• Subtask 3: 20 / 20
• Subtask 4: 20 / 20
• Subtask 5: 15 / 15