oj.uz

Submission #201153

# Submission time Handle Problem Language Result Execution time Memory
201153 2020-02-09T13:08:52 Z zscoder Olympic Bus (JOI20_ho_t4) C++17
11 / 100
 606 ms 13716 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);
		}
	}
	/*
	oriunw.dijkstra(n-1);
	for(int i=0;i<n;i++)
	{
		if(i==n-1) 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);
		}
	}
	*/
	oriunw2.dijkstra(0);
	for(int i=0;i<n;i++)
	{
		if(i==0) continue;
		if(oriunw2.par[i]!=-1)
		{
			//cerr<<oriunw.par[i]<<' '<<i<<' '<<ma[{oriunw.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
0 / 5.0

# Verdict Execution time Memory Grader output
1 Correct 39 ms 1016 KB Output is correct
2 Correct 22 ms 888 KB Output is correct
3 Correct 41 ms 1016 KB Output is correct
4 Correct 43 ms 1016 KB Output is correct
5 Correct 9 ms 632 KB Output is correct
6 Correct 19 ms 828 KB Output is correct
7 Correct 5 ms 376 KB Output is correct
8 Correct 5 ms 376 KB Output is correct
9 Correct 6 ms 556 KB Output is correct
10 Correct 54 ms 1016 KB Output is correct
11 Correct 41 ms 1016 KB Output is correct
12 Incorrect 45 ms 1016 KB Output isn't correct
13 Halted 0 ms 0 KB -

Subtask #2
11.0 / 11.0

# Verdict Execution time Memory Grader output
1 Correct 76 ms 10976 KB Output is correct
2 Correct 75 ms 10724 KB Output is correct
3 Correct 75 ms 10728 KB Output is correct
4 Correct 16 ms 1144 KB Output is correct
5 Correct 15 ms 888 KB Output is correct
6 Correct 14 ms 760 KB Output is correct
7 Correct 15 ms 760 KB Output is correct
8 Correct 5 ms 376 KB Output is correct
9 Correct 74 ms 11236 KB Output is correct
10 Correct 86 ms 11496 KB Output is correct
11 Correct 80 ms 11004 KB Output is correct
12 Correct 74 ms 10724 KB Output is correct
13 Correct 76 ms 11104 KB Output is correct
14 Correct 73 ms 12264 KB Output is correct

Subtask #3
0 / 21.0

# Verdict Execution time Memory Grader output
1 Correct 37 ms 1016 KB Output is correct
2 Correct 17 ms 760 KB Output is correct
3 Correct 398 ms 10944 KB Output is correct
4 Correct 18 ms 760 KB Output is correct
5 Correct 546 ms 13196 KB Output is correct
6 Correct 5 ms 376 KB Output is correct
7 Correct 5 ms 280 KB Output is correct
8 Correct 542 ms 13564 KB Output is correct
9 Correct 606 ms 13388 KB Output is correct
10 Correct 467 ms 12760 KB Output is correct
11 Correct 445 ms 12812 KB Output is correct
12 Correct 412 ms 13500 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 482 ms 13716 KB Output is correct
20 Incorrect 440 ms 13028 KB Output isn't correct
21 Halted 0 ms 0 KB -

Subtask #4
0 / 63.0

# Verdict Execution time Memory Grader output
1 Correct 39 ms 1016 KB Output is correct
2 Correct 22 ms 888 KB Output is correct
3 Correct 41 ms 1016 KB Output is correct
4 Correct 43 ms 1016 KB Output is correct
5 Correct 9 ms 632 KB Output is correct
6 Correct 19 ms 828 KB Output is correct
7 Correct 5 ms 376 KB Output is correct
8 Correct 5 ms 376 KB Output is correct
9 Correct 6 ms 556 KB Output is correct
10 Correct 54 ms 1016 KB Output is correct
11 Correct 41 ms 1016 KB Output is correct
12 Incorrect 45 ms 1016 KB Output isn't correct
13 Halted 0 ms 0 KB -