Submission #1159652

#	Time	Username	Problem	Language	Result	Execution time	Memory
1159652		gohchingjayk	3D Histogram (COCI20_histogram)	C++20	20 / 110	2594 ms	28484 KiB

histogram

#include <bits/stdc++.h>

using namespace std;
using ll = long long;
#define int ll

constexpr int INF = 1ull << 60;
int widths[200000 + 5], heights[200000 + 5];

struct Node {
	Node *left = nullptr, *right = nullptr;
	int l, r, m;
	int width, height;
	
	Node(int a, int b) {
		l = a, r = b, m = (l + r) >> 1;
		if (l == r) {
			width = widths[l];
			height = heights[l];
		}
		else {
			left = new Node(l, m);
			right = new Node(m + 1, r);
			width = min(left->width, right->width);
			height = min(left->height, right->height);
		}
	}
	
	pair<int, int> rmq(int a, int b) {
		if (a <= l && r <= b) return pair{width, height};
		if (r < a || b < l) return {INF, INF};
		auto [lw, lh] = left->rmq(a, b);
		auto [rw, rh] = right->rmq(a, b);
		return pair{min(lw, rw), min(lh, rh)};
	}
};

Node *segtree;
int N;
signed main() {
	ios_base::sync_with_stdio(false); cin.tie(nullptr); cout.tie(nullptr);
	cin >> N;
	for (int i = 0; i < N; ++i) cin >> widths[i] >> heights[i];
	
	segtree = new Node(0, N - 1);
	
	int ans = -1;
	for (int i = 0; i < N; ++i) {
		for (int j = i; j < N; ++j) {
			auto [width, height] = segtree->rmq(i, j);
			ans = max(ans, width * height * (j - i + 1));
		}
	}
	cout << ans;
}

• Subtask 1: 20 / 20
• Subtask 2: 0 / 90