Submission #745308

#	Time	Username	Problem	Language	Result	Execution time	Memory
745308		gnu	Travelling Merchant (APIO17_merchant)	C++14	100 / 100	90 ms	4556 KiB

merchant

#include <iostream>
#include <vector>
using namespace std;

// APIO 2017 Merchant
vector<vector<long long>> d, max_delta, d1;
struct node {
	long long v, w;
};
vector<vector<node>> gp;
vector<vector<long long>> b, s;
int main()
{
	ios_base::sync_with_stdio(false); cin.tie(nullptr);
	int n, m, k; cin >> n >> m >> k;
	gp = vector<vector<node>>(n);
	d = vector<vector<long long>>(n, vector<long long> (n, 1e18));
	b = s = vector<vector<long long>>(n, vector<long long>(k));
	for (int i = 0; i < n; ++i) {
		for (int j = 0; j < k; ++j) {
			cin >> b[i][j] >> s[i][j];
		}
	}
	vector<pair<int, int>> edges;
	for (int i = 0; i < m; ++i) {
		int u, v, w; cin >> u >> v >> w;
		--u, --v;
		gp[u].push_back({ v, w });
		d[u][v] = w;
		edges.push_back({ u, v });
	}
	//return 0;
	for (int k = 0; k < n; ++k) {
		for (int i = 0; i < n; ++i) {
			for (int j = 0; j < n; ++j) {
				 d[i][j] = min(d[i][j], d[i][k] + d[k][j]);
			}
		}
	}
	max_delta = vector<vector<long long>>(n, vector<long long>(n));
	for (int p = 0; p < k; ++p) {
		for (int i = 0; i < n; ++i) {
			for (int j = 0; j < n; ++j) {
				if (s[j][p] == -1 || b[i][p] == -1) continue;
				max_delta[i][j] = max(max_delta[i][j], s[j][p] - b[i][p]);
			}
		}
	}
	// p/t >= m
	//p >= t*m;
	// p - t*m >= 0
	d1 = vector<vector<long long>> (n, vector<long long>(n, -1e18));
	long long l = 0, r = 1e11;
	while (l + 1 < r) {
		long long m = (l + r) / 2;
		for (int i = 0; i < n; ++i) {
			for (int j = 0; j < n; ++j) {
				int u = i;
				int v = j;
				long long p = 1e18 / m;
				d1[u][v] = max_delta[u][v] - m * min(p, d[u][v]);
			}
		}
		for (int k = 0; k < n; ++k) {
			for (int i = 0; i < n; ++i) {
				for (int j = 0; j < n; ++j) {
					d1[i][j] = max(d1[i][j], d1[i][k] + d1[k][j]);
				}
			}
		}
		bool f = 0;
		for (int i = 0; i < n; ++i) if (d1[i][i] >= 0) f = 1;
		d1 = vector<vector<long long>>(n, vector<long long>(n, -1e18));
		if (f) l = m;
		else r = m;
	}
	cout << l << '\n';
}

• Subtask 1: 12 / 12
• Subtask 2: 21 / 21
• Subtask 3: 33 / 33
• Subtask 4: 34 / 34