Submission #38112

#	Time	Username	Problem	Language	Result	Execution time	Memory
38112		shash42	Ferries (NOI13_ferries)	C++11	40 / 40	803 ms	28872 KiB

ferries

#include<iostream>
#include<algorithm>
#include<vector>
#include<queue>
#define pii pair<int, int>
#define pb push_back
#define mp make_pair

using namespace std;

struct indij
{
	int dest, w, e;
};
struct nsort
{
	bool operator()(const indij &a, const indij &b)
	{
		if(a.w==b.w) return a.dest>b.dest;
		return a.w>b.w;
	}
};
struct desc
{
	bool operator()(const int &a, const int &b)
	{
		return a>b;
	}
};
priority_queue<indij, vector<indij>, nsort> pq;
int n, m, ptr[100005], visited[100005], rd[100005], edge[300005], d[100005];
vector< pii > radj[100005];
vector<int> wts[100005];
void dijkstra(int node)
{
	//cout << node << endl;
	visited[node]=1;
	for(int i = 0; i < radj[node].size(); i++)
	{
		int child=radj[node][i].first;
		int ej=radj[node][i].second;
		if(edge[ej]==-1)
		{
			indij nxt;
			nxt.dest=child;
			edge[ej]=wts[nxt.dest][ptr[nxt.dest]++];
			nxt.w=rd[node]+edge[ej];
			nxt.e=ej;
			pq.push(nxt);
		}		
	}
	int nxt=-1;
	while(pq.size()>0)
	{
		if(visited[pq.top().dest]==0)
		{
			nxt=pq.top().dest;
			rd[nxt]=pq.top().w;
			pq.pop();
			break;
		}
		pq.pop();
	}
	if(nxt!=-1) dijkstra(nxt);
}
int main()
{
	cin >> n >> m;
	for(int i = 0; i < m; i++)
	{
		int u, v, w;
		cin >> u >> v >> w;
		radj[v].pb(mp(u, i));
		wts[u].pb(w);
		edge[i]=-1;
	}
	for(int i = 1; i <= n; i++)
	{
		sort(wts[i].begin(), wts[i].end(), desc());
	}
	rd[n]=0;
	dijkstra(n);
	cout << rd[1];
}

Compilation message (stderr)

ferries.cpp: In function 'void dijkstra(int)':
ferries.cpp:38:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for(int i = 0; i < radj[node].size(); i++)
                   ^

• Subtask 1: 7 / 7
• Subtask 2: 10 / 10
• Subtask 3: 11 / 11
• Subtask 4: 12 / 12