oj.uz

Submission #201144

# Submission time Handle Problem Language Result Execution time Memory
201144 2020-02-09T12:24:58 Z zscoder Olympic Bus (JOI20_ho_t4) C++17
37 / 100
 1000 ms 13584 KB 
#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
 
using namespace std;
using namespace __gnu_pbds;
 
#define fi first
#define se second
#define mp make_pair
#define pb push_back
#define fbo find_by_order
#define ook order_of_key
 
typedef long long ll;
typedef pair<int,int> ii;
typedef vector<int> vi;
typedef long double ld; 
typedef tree<int, null_type, less<int>, rb_tree_tag, tree_order_statistics_node_update> pbds;
set<int> S;

struct Graph
{
	struct edge
	{
		int v; ll weight; int id;
	};
	vector<vector<edge> > adj;
	int n;
	
	Graph(int _n)
	{
		adj.resize(_n);
		n = _n;
	}
	
	void addedge(int u, int v, ll c, int id)
	{
		edge tmp;
		tmp.v = v; tmp.weight = c; tmp.id=id;
		adj[u].pb(tmp);
	}
	
	void reset()
	{
		adj.clear();
	}
	
	vector<ll> dist;
	vi par;
	
	void bfs(int s)
	{
		ll INFI = ll(1e18);
		dist.assign(n, INFI);
		par.assign(n, -1);
		dist[s] = 0; par[s] = -1;
		queue<int> q; q.push(s);
		while(!q.empty())
		{
			int u = q.front(); q.pop();
			for(int i = 0; i < adj[u].size(); i++)
			{
				int v = adj[u][i].v;
				if(dist[v] >= INFI)
				{
					dist[v] = dist[u] + 1;
					par[v] = u;
					q.push(v);
				}
			}
		}
	}
	
	void bfs01(int s)
	{
		ll INFI = ll(1e18);
		dist.assign(n, INFI);
		par.assign(n, -1);
		dist[s] = 0; par[s] = -1;
		deque<int> q; q.pb(s);
		while(!q.empty())
		{
			int u = q.front(); q.pop_front();
			for(int i = 0; i < adj[u].size(); i++)
			{
				int v = adj[u][i].v; ll w = adj[u][i].weight;
				if(dist[v] >= INFI)
				{
					if(w == 1)
					{
						dist[v] = dist[u] + 1;
						par[v] = u;
						q.push_back(v);
					}
					else
					{
						dist[v] = dist[u];
						par[v] = u;
						q.push_front(v);
					}
				}
			}
		}
	}
	
	void dijkstra(int s, int mode=1)
	{
		ll INFI = ll(1e18);
		dist.clear();
		dist.assign(n, INFI);
		par.assign(n, -1);
		dist[s] = 0; par[s] = -1;
		priority_queue<ii, vector<ii>, greater<ii> > pq;
		pq.push(ii(0, s));
		while(!pq.empty())
		{
			int u = pq.top().se; ll d = pq.top().fi; pq.pop();
			for(int i = 0; i < adj[u].size(); i++)
			{
				int v = adj[u][i].v; ll w = adj[u][i].weight;
				if(d + w < dist[v])
				{
					dist[v] = d + w;
					par[v] = u;
					//cerr<<"ADD "<<adj[u][i].id<<'\n';
					//if(mode) S.insert(adj[u][i].id);
					pq.push(ii(dist[v], v));
				}
			}
		}
	}
	
	vector<vector<ll> > d;
	
	void Floyd()
	{
		ll INFIN = ll(1e18);
		d.resize(n);
		for(int i = 0; i < n; i++)
		{
			d[i].assign(n, INFIN);
		}
		for(int i = 0; i < n; i++)
		{
			for(int j = 0; j < adj[i].size(); j++)
			{
				d[i][adj[i][j].v] = min(d[i][adj[i][j].v],adj[i][j].weight);
			}
			d[i][i] = 0;
		}
		for(int k = 0; k < n; k++)
		{
			for(int i = 0; i < n; i++)
			{
				for(int j = 0; j < n; j++)
				{
					d[i][j] = min(d[i][j], d[i][k] + d[k][j]);
				}
			}
		}
	}
};

ll D[55555];
vector<pair<ii,ii> > edges;
int n,m; 
ll res=ll(1e18);

void test(int id)
{
	Graph G(n);
	for(int i=0;i<m;i++)
	{
		int u=edges[i].fi.fi; int v=edges[i].fi.se;
		if(i==id) swap(u,v);
		G.addedge(u,v,edges[i].se.fi,edges[i].se.se);
	}
	G.dijkstra(0,0);
	ll ans = G.dist[n-1];
	G.dijkstra(n-1,0);
	ans+=G.dist[0];
	ans+=D[id];
	res=min(res,ans);
}

int main()
{
	ios_base::sync_with_stdio(0); cin.tie(0);
	//freopen("olympic-bus.in","r",stdin);
	cin>>n>>m;
	Graph ori(n),oriunw(n),oriunw2(n);
	vector<ii> VV;
	int all0=1;
	map<ii,ii> ma;
	for(int i=0;i<m;i++)
	{
		int u,v,c,d;
		cin>>u>>v>>c>>d;
		if(c!=0) all0=0;
		VV.pb({d,i});
		u--; v--;
		if(ma.find({u,v})==ma.end())
		{
			ma[{u,v}]={c+d,i};
		}
		else
		{
			ma[{u,v}]=min(ma[{u,v}],{c+d,i});
		}
		D[i]=d;
		edges.pb({{u,v},{c,d}});
		ori.addedge(u,v,c,i);
		oriunw.addedge(u,v,c,i);
		oriunw.addedge(v,u,c+d,i);
		oriunw2.addedge(v,u,c,i);
		oriunw2.addedge(u,v,c+d,i);
	}
	int sub2=1;
	if(m%2==0)
	{
		for(int i=0;i<m;i+=2)
		{
			int a1 = edges[i].se.se;
			int a2 = edges[i+1].se.se;
			edges[i].se.se=edges[i+1].se.se=0;
			if(edges[i]!=edges[i+1]) sub2=0;
			edges[i].se.se=a1; edges[i+1].se.se=a2;
		}
	}
	else sub2=0;
	ori.Floyd();
	ll as = ori.d[0][n-1]+ori.d[n-1][0];
	oriunw.dijkstra(0);
	for(int i=0;i<n;i++)
	{
		if(i==0) continue;
		if(oriunw.par[i]!=-1)
		{
			//cerr<<oriunw.par[i]<<' '<<i<<' '<<ma[{oriunw.par[i],i}].se<<endl;
			S.insert(ma[{oriunw.par[i],i}].se);
		}
	}
	oriunw2.dijkstra(n-1);
	for(int i=0;i<n;i++)
	{
		if(i==n-1) continue;
		if(oriunw2.par[i]!=-1)
		{
			//cerr<<oriunw2.par[i]<<' '<<i<<' '<<ma[{oriunw2.par[i],i}].se<<endl;
			S.insert(ma[{oriunw2.par[i],i}].se);
		}
	}
	res=min(res,as);
	//test(ma[{141,15}].se);
	//assert(sub2);
	if(sub2)
	{
		for(auto E:edges)
		{
			int u=E.fi.fi; int v=E.fi.se; 
			ll c=E.se.fi; ll d=E.se.se;
			//should i add the edge v->u
			res=min(res,d+ori.d[0][n-1]+ori.d[n-1][v]+c+ori.d[u][0]);
			res=min(res,d+ori.d[0][v]+c+ori.d[u][n-1]+ori.d[n-1][0]);
			res=min(res,d+ori.d[0][v]+c+ori.d[u][n-1]+ori.d[n-1][v]+c+ori.d[u][0]);
			res=min(res,ori.d[0][n-1]+ori.d[n-1][0]);
		}
	}
	else
	{
		
		set<int> nw;
		for(int s:S)
		{
			int u=edges[s].fi.fi; int v=edges[s].fi.se;
			nw.insert(ma[{u,v}].se);
		}
		//cerr<<nw.size()<<endl;
		for(int s:nw) 
		{
			test(s);
		}
	}
	if(res>=ll(1e18)) res=-1;
	cout<<res<<'\n';
}

Compilation message

ho_t4.cpp: In member function 'void Graph::bfs(int)':
ho_t4.cpp:62:21: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
    for(int i = 0; i < adj[u].size(); i++)
                   ~~^~~~~~~~~~~~~~~
ho_t4.cpp: In member function 'void Graph::bfs01(int)':
ho_t4.cpp:85:21: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
    for(int i = 0; i < adj[u].size(); i++)
                   ~~^~~~~~~~~~~~~~~
ho_t4.cpp: In member function 'void Graph::dijkstra(int, int)':
ho_t4.cpp:119:21: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
    for(int i = 0; i < adj[u].size(); i++)
                   ~~^~~~~~~~~~~~~~~
ho_t4.cpp: In member function 'void Graph::Floyd()':
ho_t4.cpp:146:21: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
    for(int j = 0; j < adj[i].size(); j++)
                   ~~^~~~~~~~~~~~~~~
ho_t4.cpp: In function 'int main()':
ho_t4.cpp:194:6: warning: variable 'all0' set but not used [-Wunused-but-set-variable]
  int all0=1;
      ^~~~

Subtask #1
5.0 / 5.0

# Verdict Execution time Memory Grader output
1 Correct 39 ms 1016 KB Output is correct
2 Correct 17 ms 812 KB Output is correct
3 Correct 39 ms 1016 KB Output is correct
4 Correct 41 ms 1016 KB Output is correct
5 Correct 10 ms 632 KB Output is correct
6 Correct 23 ms 760 KB Output is correct
7 Correct 5 ms 376 KB Output is correct
8 Correct 5 ms 280 KB Output is correct
9 Correct 6 ms 504 KB Output is correct
10 Correct 50 ms 1016 KB Output is correct
11 Correct 54 ms 1016 KB Output is correct
12 Correct 48 ms 1016 KB Output is correct
13 Correct 37 ms 1016 KB Output is correct
14 Correct 36 ms 1016 KB Output is correct
15 Correct 37 ms 1020 KB Output is correct
16 Correct 38 ms 1016 KB Output is correct

Subtask #2
11.0 / 11.0

# Verdict Execution time Memory Grader output
1 Correct 72 ms 10980 KB Output is correct
2 Correct 72 ms 10852 KB Output is correct
3 Correct 74 ms 10724 KB Output is correct
4 Correct 23 ms 1144 KB Output is correct
5 Correct 16 ms 1016 KB Output is correct
6 Correct 14 ms 888 KB Output is correct
7 Correct 14 ms 760 KB Output is correct
8 Correct 5 ms 376 KB Output is correct
9 Correct 73 ms 11108 KB Output is correct
10 Correct 74 ms 11364 KB Output is correct
11 Correct 81 ms 10980 KB Output is correct
12 Correct 68 ms 10724 KB Output is correct
13 Correct 70 ms 11108 KB Output is correct
14 Correct 71 ms 12388 KB Output is correct

Subtask #3
21.0 / 21.0

# Verdict Execution time Memory Grader output
1 Correct 35 ms 1016 KB Output is correct
2 Correct 17 ms 760 KB Output is correct
3 Correct 502 ms 10932 KB Output is correct
4 Correct 24 ms 764 KB Output is correct
5 Correct 602 ms 13168 KB Output is correct
6 Correct 5 ms 376 KB Output is correct
7 Correct 5 ms 376 KB Output is correct
8 Correct 526 ms 13488 KB Output is correct
9 Correct 562 ms 13312 KB Output is correct
10 Correct 696 ms 12880 KB Output is correct
11 Correct 688 ms 12732 KB Output is correct
12 Correct 671 ms 13488 KB Output is correct
13 Correct 5 ms 376 KB Output is correct
14 Correct 5 ms 376 KB Output is correct
15 Correct 5 ms 376 KB Output is correct
16 Correct 5 ms 376 KB Output is correct
17 Correct 5 ms 376 KB Output is correct
18 Correct 5 ms 376 KB Output is correct
19 Correct 686 ms 13584 KB Output is correct
20 Correct 617 ms 13300 KB Output is correct
21 Correct 627 ms 12800 KB Output is correct
22 Correct 669 ms 12800 KB Output is correct

Subtask #4
0 / 63.0

# Verdict Execution time Memory Grader output
1 Correct 39 ms 1016 KB Output is correct
2 Correct 17 ms 812 KB Output is correct
3 Correct 39 ms 1016 KB Output is correct
4 Correct 41 ms 1016 KB Output is correct
5 Correct 10 ms 632 KB Output is correct
6 Correct 23 ms 760 KB Output is correct
7 Correct 5 ms 376 KB Output is correct
8 Correct 5 ms 280 KB Output is correct
9 Correct 6 ms 504 KB Output is correct
10 Correct 50 ms 1016 KB Output is correct
11 Correct 54 ms 1016 KB Output is correct
12 Correct 48 ms 1016 KB Output is correct
13 Correct 37 ms 1016 KB Output is correct
14 Correct 36 ms 1016 KB Output is correct
15 Correct 37 ms 1020 KB Output is correct
16 Correct 38 ms 1016 KB Output is correct
17 Correct 72 ms 10980 KB Output is correct
18 Correct 72 ms 10852 KB Output is correct
19 Correct 74 ms 10724 KB Output is correct
20 Correct 23 ms 1144 KB Output is correct
21 Correct 16 ms 1016 KB Output is correct
22 Correct 14 ms 888 KB Output is correct
23 Correct 14 ms 760 KB Output is correct
24 Correct 5 ms 376 KB Output is correct
25 Correct 73 ms 11108 KB Output is correct
26 Correct 74 ms 11364 KB Output is correct
27 Correct 81 ms 10980 KB Output is correct
28 Correct 68 ms 10724 KB Output is correct
29 Correct 70 ms 11108 KB Output is correct
30 Correct 71 ms 12388 KB Output is correct
31 Correct 35 ms 1016 KB Output is correct
32 Correct 17 ms 760 KB Output is correct
33 Correct 502 ms 10932 KB Output is correct
34 Correct 24 ms 764 KB Output is correct
35 Correct 602 ms 13168 KB Output is correct
36 Correct 5 ms 376 KB Output is correct
37 Correct 5 ms 376 KB Output is correct
38 Correct 526 ms 13488 KB Output is correct
39 Correct 562 ms 13312 KB Output is correct
40 Correct 696 ms 12880 KB Output is correct
41 Correct 688 ms 12732 KB Output is correct
42 Correct 671 ms 13488 KB Output is correct
43 Correct 5 ms 376 KB Output is correct
44 Correct 5 ms 376 KB Output is correct
45 Correct 5 ms 376 KB Output is correct
46 Correct 5 ms 376 KB Output is correct
47 Correct 5 ms 376 KB Output is correct
48 Correct 5 ms 376 KB Output is correct
49 Correct 686 ms 13584 KB Output is correct
50 Correct 617 ms 13300 KB Output is correct
51 Correct 627 ms 12800 KB Output is correct
52 Correct 669 ms 12800 KB Output is correct
53 Correct 998 ms 12988 KB Output is correct
54 Execution timed out 1086 ms 13468 KB Time limit exceeded
55 Halted 0 ms 0 KB -