Submission #250858

#	Time	Username	Problem	Language	Result	Execution time	Memory
250858		atoiz	Travelling Merchant (APIO17_merchant)	C++14	0 / 100	88 ms	1400 KiB

merchant

/*input
4 5 2
10 9 5 2
6 4 20 15
9 7 10 9
-1 -1 16 11
1 2 3
2 3 3
1 4 1
4 3 1
3 1 1
*/
#include <iostream>
#include <vector>
#include <algorithm>
#include <cstdio>
#include <cstring>

using namespace std;

const int MAXN = 105, MAXK = 1005, INF = 1001001000;
int N, M, K;
int rawdist[MAXN][MAXN], gain[MAXN][MAXN], buy[MAXN][MAXK], sel[MAXN][MAXK];
long long curdist[MAXN][MAXN], dist1[MAXN];

#define FOR(i, a, b) for (int i = a; i <= b; ++i)
#define FORA(i, a) for (auto &i : a)

bool check(long long val)
{
	vector<int> V;
	FOR(i, 1, N) if (rawdist[1][i] < INF && rawdist[i][1] < INF) V.push_back(i);
	// FOR(i, 1, N) V.push_back(i);

	FORA(i, V) FORA(j, V) curdist[i][j] = rawdist[i][j] * val - gain[i][j];
	FORA(i, V) dist1[i] = curdist[1][i];

	bool cont = true;
	for (int trial = 0; cont; ++trial) {
		if (trial == N + 9) return true;
		cont = false;
		FORA(i, V) FORA(j, V) if (rawdist[i][j] < INF && dist1[i] + curdist[i][j] < dist1[j]) {
			dist1[j] = dist1[i] + curdist[i][j];
			cont = true;
		}

		FOR(i, 2, N) if (dist1[i] + curdist[i][1] <= 0) return true;
	}

	return false;
}

int main()
{
	ios_base::sync_with_stdio(0); cin.tie(0);
	cin >> N >> M >> K;
	FOR(i, 1, N) FOR(j, 1, K) cin >> buy[i][j] >> sel[i][j];
	FOR(i, 1, N) FOR(j, 1, N) rawdist[i][j] = INF;
	FOR(i, 1, N) rawdist[i][i] = 0;
	FOR(_, 0, M - 1) {
		int u, v, w;
		cin >> u >> v >> w;
		rawdist[u][v] = min(rawdist[u][v], w);
	}
	FOR(k, 1, N) FOR(i, 1, N) FOR(j, 1, N) rawdist[i][j] = min(rawdist[i][j], rawdist[i][k] + rawdist[k][j]);
	FOR(i, 1, N) FOR(j, 1, N) FOR(k, 1, K) if (~buy[i][k] && ~sel[j][k]) gain[i][j] = max(gain[i][j], sel[j][k] - buy[i][k]);

	int lo = 0, hi = INF;
	while (lo < hi) {
		int mid = (lo + hi + 1) >> 1;
		if (check(mid)) lo = mid;
		else hi = mid - 1;
	}
	cout << lo << endl;
}

• Subtask 1: 0 / 12
• Subtask 2: 0 / 21
• Subtask 3: 0 / 33
• Subtask 4: 0 / 34