Submission #104717

#	Time	Username	Problem	Language	Result	Execution time	Memory
104717		puyu_liao	Travelling Merchant (APIO17_merchant)	C++14	0 / 100	165 ms	2296 KiB

merchant

#include<bits/stdc++.h>
#include<stdint.h>
using namespace std;
#define IOS {cin.tie(0);ios_base::sync_with_stdio(false);}
#define int int64_t
#define N 105
#define K 1005
const int INF = 1e14;

int bb[N][K],ss[N][K];
int w[N][N],dis[N][N];
double dp[N][N];
bitset<N> vis;
vector<pair<int,int> > v[N];

int32_t main()
{
	IOS;
	int n,m,k,a,b,t;
	cin >> n >> m >> k;
	for(int i=1;i<=n;i++) for(int j=1;j<=k;j++) cin >> bb[i][j] >> ss[i][j];
	for(int i=0;i<m;i++){
		cin >> a >> b >> t;
		v[a].push_back({b,t});
	}
	for(int i=1;i<=n;i++){
		int *dd = dis[i];
		fill(dd+1,dd+n+1,INF);
		vis.reset(); queue<int> q;
		dd[i] = 0; q.push(i); vis[i] = 1;
		while(!q.empty()){
			int x = q.front(); q.pop();
			vis[x] = 0;
			for(auto i : v[x]) if(dd[i.first] > dd[x] + i.second){
				dd[i.first] = dd[x] + i.second;
				if(!vis[i.first]) vis[i.first]=1,q.push(i.first);
			}
		}
		for(int j=1;j<=n;j++){
			if(j != i && dd[j] != INF) {
				for(int x=1;x<=k;x++) if(ss[j][x] >= 0 && bb[i][x] >= 0) w[i][j] = max(w[i][j],ss[j][x] - bb[i][x]);
			}
			else w[i][j] = 0;
		}
	}

	
	double l=0,r = 1e16;
	for(int cnt=0;cnt<100;cnt++){
		double mm = (l+r)*0.5;
		//cout << "mm = " << mm << '\n';
		for(int i=1;i<=n;i++) for(int j=1;j<=n;j++) {
			dp[i][j] = mm*dis[i][j] - w[i][j];
		}
//		cout << "dp :\n";
//		for(int i=1;i<=n;i++,cout << '\n') for(int j=1;j<=n;j++)cout << fixed << setprecision(1) << dp[i][j] << ' '; 
		for(int x=1;x<=n;x++) for(int i=1;i<=n;i++) for(int j=1;j<=n;j++) {
			dp[i][j] = min(dp[i][j],dp[i][x] + dp[x][j]);
		}
		bool gg = false;
		for(int i=1;i<=n;i++) if(dp[i][i] < 0) gg = true;
		if(gg) l = mm;
		else r = mm;
	}
	cout << (int)(round(l)+0.5) << '\n';
  return 0;
}

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