Submission #329188

#	Time	Username	Problem	Language	Result	Execution time	Memory
329188		faresbasbs	Travelling Merchant (APIO17_merchant)	C++17	100 / 100	98 ms	4204 KiB

merchant

#include <bits/stdc++.h>
using namespace std;
const int INF = 1000000000;
long long n,m,kk,buy[101][1001],sell[101][1001],graph[101][101],graph2[101][101],profit[101][101];

void floyd(long long adj[101][101]){
	for(int k = 1 ; k <= n ; k += 1){
		for(int i = 1 ; i <= n ; i += 1){
			for(int j = 1 ; j <= n ; j += 1){
				adj[i][j] = min(adj[i][j],adj[i][k]+adj[k][j]);
			}
		}
	}
}

int main(){
	ios_base::sync_with_stdio(false);
	cout.tie(NULL);
	cin.tie(NULL);
	cin >> n >> m >> kk;
	for(int i = 1 ; i <= n ; i += 1){
		for(int j = 1 ; j <= n ; j += 1){
			graph[i][j] = INF;
		}
		for(int j = 1 ; j <= kk ; j += 1){
			cin >> buy[i][j] >> sell[i][j];
		}
	}
	for(int i = 0 ; i < m ; i += 1){
		int a,b,c;
		cin >> a >> b >> c;
		graph[a][b] = c;
	}
	floyd(graph);
	for(int i = 1 ; i <= n ; i += 1){
		for(int j = 1 ; j <= n ; j += 1){
			for(int k = 1 ; k <= kk ; k += 1){
				if(sell[j][k] != -1 && buy[i][k] != -1){
					profit[i][j] = max(profit[i][j],sell[j][k]-buy[i][k]);
				}
			}
		}
	}
	long long first = 0 , last = INF;
	while(last-first > 1){
		long long mid = (first+last)/2;
		for(int i = 1 ; i <= n ; i += 1){
			for(int j = 1 ; j <= n ; j += 1){
				graph2[i][j] = mid*graph[i][j] - profit[i][j];
			}
		}
		floyd(graph2);
		bool good = false;
		for(int i = 1 ; i <= n ; i += 1){
			if(graph2[i][i] <= 0){
				good = true;
				break;
			}
		}
		if(good){
			first = mid;
		}else{
			last = mid;
		}
	}
	cout << first << endl;
}

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