Submission #768377

#	Time	Username	Problem	Language	Result	Execution time	Memory
768377		minhcool	Cake 3 (JOI19_cake3)	C++17	100 / 100	1221 ms	21952 KiB

cake3

#define local
#ifndef local
#include ""
#endif
#include<bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
using namespace __gnu_pbds;
using namespace std;

#define int long long
#define fi first
#define se second
#define pb push_back
#define mp make_pair

typedef pair<int, int> ii;
typedef pair<ii, int> iii;
typedef pair<ii, ii> iiii;

const int N = 3e5 + 5;

const int oo = 1e18 + 7, mod = 1e9 + 7;

mt19937 rng(1);

int rnd(int l, int r){
	int temp = rng() % (r - l + 1);
	return abs(temp) + l;
}

int n, m;
ii arr[N];
int v[N], c[N];

int answer = -oo;

vector<int> diff;
int pos[N];

bool cmp(ii a, ii b){
	return a.se < b.se;
}

int lstl, lstr;

int sum[N << 2], num[N << 2];

int IT[N << 2];

void upd(int id, int l, int r, int pos, int val){
	if(l == r){
		sum[id] += diff[l] * val;
		num[id] += val;
		return;
	}
	int mid = (l + r) >> 1;
	if(pos <= mid) upd(id << 1, l, mid, pos, val);
	else upd(id << 1 | 1, mid + 1, r, pos, val);
	sum[id] = sum[id << 1] + sum[id << 1 | 1];
	num[id] = num[id << 1] + num[id << 1 | 1];
}

int tol(int id, int l, int r, int rem){
	if(l == r){
		if(rem > num[id]) return -oo;
		return rem * diff[l];
	}
	int mid = (l + r) >> 1;
	if(num[id << 1] >= rem) return tol(id << 1, l, mid, rem);
	else return sum[id << 1] + tol(id << 1 | 1, mid + 1, r, rem - num[id << 1]);
}

void mov(int le, int ri){
	while(lstl > le){
		lstl--;
		upd(1, 1, diff.size() - 1, pos[lstl], 1);
	}
	while(lstr < ri){
		lstr++;
		upd(1, 1, diff.size() - 1, pos[lstr], 1);
	}
	while(lstl < le){
		upd(1, 1, diff.size() - 1, pos[lstl], -1);
		lstl++;
	}
	while(lstr > ri){
		upd(1, 1, diff.size() - 1, pos[lstr], -1);
		lstr--;
	}
}

int get(){
	return tol(1, 1, diff.size() - 1, m - 2);
}

void dncdp(int l, int r, int optl, int optr){
	if(l > r) return;
	int temp1 = lstl, temp2 = lstr;
	if(optl == optr){
		for(int i = l; i <= r; i++){
			mov(optl + 1, i - 1);
		//	cout << optl << " " << i << "\n";
			answer = max(answer, get() + v[optl] + 2 * c[optl] + v[i] - 2 * c[i]);	
		}
		return;
	}
	int mid = (l + r) >> 1;
	ii maxi = {-oo, -oo};
	for(int i = optl; (i <= optr) && ((i + 2) <= mid); i++){
		mov(i + 1, mid - 1);
		maxi = max(maxi, {get() + v[i] + 2 * c[i] + v[mid] - 2 * c[mid], i});
	}
	//cout << maxi.se << " " << mid << "\n";
	answer = max(answer, maxi.fi);
	dncdp(l, mid - 1, optl, maxi.se);
	dncdp(mid + 1, r, maxi.se, optr);
	mov(temp1, temp2);
}

#ifdef local
void process(){
	cin >> n >> m;
	for(int i = 1; i <= n; i++) cin >> arr[i].fi >> arr[i].se;
	sort(arr + 1, arr + n + 1, cmp);
	for(int i = 1; i <= n; i++){
		v[i] = arr[i].fi;
		c[i] = arr[i].se;
	}
	diff.pb(oo);
	for(int i = 1; i <= n; i++) diff.pb(arr[i].fi);
	sort(diff.begin(), diff.end());
	diff.resize(unique(diff.begin(), diff.end()) - diff.begin());
	reverse(diff.begin(), diff.end());
	for(int i = 1; i <= n; i++){
		int le = 1, ri = diff.size() - 1;
		while(le < ri){
			int mid = (le + ri) >> 1;
			if(diff[mid] > v[i]) le = mid + 1;
			else ri = mid;
		}	
		pos[i] = le;
	}
	lstl = 1, lstr = 0;
	dncdp(m, n, 1, n - m + 1);
	cout << answer;
}

signed main(){
	ios_base::sync_with_stdio(0);
	cin.tie(0);
	process();
}
#endif

• Subtask 1: 5 / 5
• Subtask 2: 19 / 19
• Subtask 3: 76 / 76