Submission #97215

#	Time	Username	Problem	Language	Result	Execution time	Memory
97215		E869120	Travelling Merchant (APIO17_merchant)	C++14	100 / 100	806 ms	2552 KiB

merchant

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

long long N, M, K, B[109][1009], S[109][1009];
long long dist[109][109], V[109][109], D[109][109], col[109]; long double dp[109], e[109][109];
vector<int>G[109], I;

void dfs(int pos) {
	if (col[pos] == 1) return;
	col[pos] = 1;
	for (int i = 0; i < G[pos].size(); i++) dfs(G[pos][i]);
}

bool solve(long double c) {
	for (int i = 1; i <= N; i++) {
		for (int j = 1; j <= N; j++) {
			if (dist[i][j] == (1LL << 60) || V[i][j] == -(1LL << 60)) { e[i][j] = 1e18; continue; }
			e[i][j] = 1.0L * c * dist[i][j] - 1.0L * V[i][j];
		}
	}
	for (int i = 1; i <= N; i++) dp[i] = (1LL << 60);
	for (int i = 0; i < I.size(); i++) dp[I[i]] = 0;

	for (int i = 1; i <= 2 * N; i++) {
		for (int j = 1; j <= N; j++) {
			for (int k = 1; k <= N; k++) {
				dp[k] = min(dp[k], dp[j] + e[j][k]);
			}
		}
	}
	vector<long double>E1; for (int i = 1; i <= N; i++) E1.push_back(dp[i]);

	for (int i = 1; i <= N; i++) {
		for (int j = 1; j <= N; j++) {
			for (int k = 1; k <= N; k++) {
				dp[k] = min(dp[k], dp[j] + e[j][k]);
			}
		}
	}
	vector<long double>E2; for (int i = 1; i <= N; i++) E2.push_back(dp[i]);

	if (E1 == E2) return false;
	return true;
}

int main() {
	cin >> N >> M >> K;
	for (int i = 1; i <= N; i++) { for (int j = 1; j <= N; j++) { dist[i][j] = (1LL << 60); D[i][i] = 1; } }
	for (int i = 1; i <= N; i++) {
		for (int j = 1; j <= K; j++) cin >> B[i][j] >> S[i][j];
	}
	for (int i = 1; i <= M; i++) {
		long long a1, a2, a3; cin >> a1 >> a2 >> a3;
		dist[a1][a2] = a3;
	}
	for (int k = 1; k <= N; k++) {
		for (int i = 1; i <= N; i++) {
			for (int j = 1; j <= N; j++) dist[i][j] = min(dist[i][j], dist[i][k] + dist[k][j]);
		}
	}
	for (int i = 1; i <= N; i++) {
		for (int j = 1; j <= N; j++) {
			long long Benq = 0;
			for (int k = 1; k <= K; k++) {
				if (S[j][k] == -1 || B[i][k] == -1) continue;
				Benq = max(Benq, S[j][k] - B[i][k]);
			}
			if (dist[i][j] != (1LL << 60)) { V[i][j] = Benq; D[i][j] = 1; }
			else V[i][j] = -(1LL << 60);
		}
	}
	for (int k = 1; k <= N; k++) {
		for (int i = 1; i <= N; i++) {
			for (int j = 1; j <= N; j++) {
				if (D[i][k] == 1 && D[k][j] == 1) D[i][j] = 1;
			}
		}
	}
	for (int i = 1; i <= N; i++) {
		for (int j = 1; j <= N; j++) { if (D[i][j] == 1 && D[j][i] == 1) G[i].push_back(j); }
	}
	for (int i = 1; i <= N; i++) {
		if (col[i] == 1) continue;
		I.push_back(i); dfs(i);
	}

	long long L = 1, R = (1LL << 30), MM, maxn = 0;
	for (int i = 0; i < 35; i++) {
		MM = (L + R) / 2;
		bool t = solve(1.0L * MM - 1e-10);
		if (t == true) { L = MM; maxn = max(maxn, MM); }
		else { R = MM; }
	}
	cout << maxn << endl;
	return 0;
}

Compilation message (stderr)

merchant.cpp: In function 'void dfs(int)':
merchant.cpp:13:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for (int i = 0; i < G[pos].size(); i++) dfs(G[pos][i]);
                  ~~^~~~~~~~~~~~~~~
merchant.cpp: In function 'bool solve(long double)':
merchant.cpp:24:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for (int i = 0; i < I.size(); i++) dp[I[i]] = 0;
                  ~~^~~~~~~~~~

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