Submission #497388

#	Time	Username	Problem	Language	Result	Execution time	Memory
497388		pavement	Cake 3 (JOI19_cake3)	C++17	0 / 100	1 ms	340 KiB

cake3

#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
using namespace std;
using namespace __gnu_pbds;
#ifdef _WIN32
#define getchar_unlocked _getchar_nolock
#endif
#define int long long
#define mp make_pair
#define mt make_tuple
#define pb push_back
#define ppb pop_back
#define eb emplace_back
#define g0(a) get<0>(a)
#define g1(a) get<1>(a)
#define g2(a) get<2>(a)
#define g3(a) get<3>(a)
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
typedef double db;
typedef long long ll;
typedef long double ld;
typedef pair<int, int> ii;
typedef tuple<int, int, int> iii;
typedef tuple<int, int, int, int> iiii;
typedef tree<ii, null_type, less<ii>, rb_tree_tag, tree_order_statistics_node_update> ordered_set;

int L, R, N, M, ans = LLONG_MIN, V[200005], DV[200005], RV[200005], C[200005];
ii T[200005], ft[200005];
vector<int> disc;
priority_queue<int, vector<int>, greater<int> > pq;

inline int ls(int x) { return x & -x; }

void upd(int p, int a, int b) {
	for (; p <= disc.size(); p += ls(p))
		ft[p].first += a, ft[p].second += b;
}

void add(int x) {
	upd(DV[x], V[x], 1);
}

void del(int x) {
	upd(DV[x], -V[x], -1);
}

int k_largest(int k) {
	int curr = 0, cnt = 0, cnt2 = 0;
	for (int i = 18; i >= 0; i--)
		if (curr + (1 << i) <= disc.size() && cnt + ft[curr + (1 << i)].second <= k) {
			cnt += ft[curr + (1 << i)].second;
			cnt2 += ft[curr + (1 << i)].first;
			curr += (1 << i);
		}
	return cnt2 + (k - cnt) * RV[curr];
}

void shift(int l, int r) {
	while (l < L) add(--L);
	while (r > R) add(++R);
	while (l > L) del(L++);
	while (r < R) del(R--);
}

void dnc(int l, int r, int x, int y) {
	if (l > r) return;
	int m = (l + r) >> 1, sum = 0, opt = LLONG_MIN, pos = -1;
	for (; !pq.empty(); pq.pop());
	for (int i = min(m, y); i >= x; i--) {
		shift(i, m);
		sum = k_largest(M);
		if (m - i + 1 >= M && sum - 2 * (C[m] - C[i]) > opt) {
			opt = sum - 2 * (C[m] - C[i]);
			pos = i;
		}
	}
	assert(pos != -1);
	ans = max(ans, opt);
	dnc(l, m - 1, x, pos);
	dnc(m + 1, r, pos, y);
}

main() {
	ios::sync_with_stdio(0);
	cin.tie(0);
	cin >> N >> M;
	for (int i = 1; i <= N; i++) {
		cin >> T[i].second >> T[i].first;
		disc.pb(T[i].second);
	}
	sort(T + 1, T + 1 + N);
	sort(disc.begin(), disc.end());
	for (int i = 1; i <= N; i++) {
		tie(C[i], V[i]) = T[i];
		DV[i] = disc.size() - (lower_bound(disc.begin(), disc.end(), V[i]) - disc.begin() + 1) + 1;
		RV[DV[i]] = V[i];
	}
	L = R = 1;
	add(1);
	dnc(M, N, 1, N);
	cout << ans << '\n';
}

Compilation message (stderr)

cake3.cpp: In function 'void upd(long long int, long long int, long long int)':
cake3.cpp:36:11: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   36 |  for (; p <= disc.size(); p += ls(p))
      |         ~~^~~~~~~~~~~~~~
cake3.cpp: In function 'long long int k_largest(long long int)':
cake3.cpp:51:23: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   51 |   if (curr + (1 << i) <= disc.size() && cnt + ft[curr + (1 << i)].second <= k) {
      |       ~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~
cake3.cpp: At global scope:
cake3.cpp:84:1: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
   84 | main() {
      | ^~~~

• Subtask 1: 0 / 5
• Subtask 2: 0 / 19
• Subtask 3: 0 / 76