oj.uz

Submission #201160

# Submission time Handle Problem Language Result Execution time Memory
201160 2020-02-09T13:26:41 Z zscoder Olympic Bus (JOI20_ho_t4) C++17
37 / 100
 1000 ms 13788 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<ll,ll> 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;
					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]);
				}
			}
		}
	}
};

const int MAXV = 200;		// maximum value of vertex
const ll INF = ll(1e18)+10;		// infinity value used instead of INT_MAX for relax may overflow
const int INVALID = 0xDEADF00D;	// special value to record negetive cycle condiction

class LIB_SPFA{
public:

	LIB_SPFA(int v=MAXV, int e=MAXV*(MAXV-1)) 
		: neg_cycle(false), checked_start(INVALID), Vnum(v), Enum(e), edge(Vnum+1), prev(Vnum+1), dis(Vnum+1)
	{}

	void add_edge(int src, int dst, int weight)
	{
		edge[src].push_back(EDGE(dst,weight));

		checked_start = INVALID;
	}

	bool contains_neg_cycle(int src=1)
	{
		if(checked_start == INVALID)
			SPFA(src);
		return neg_cycle;
	}

	ll get_dis(int src, int dst)
	{
		if(contains_neg_cycle(src))
			return INVALID;
		if(checked_start != src)
			SPFA(src);
		return dis[dst];
	}

	const vector<int>& getPrev() const {return prev;}

	struct EDGE{
		EDGE(int n, int w):next(n),w(w){}
		int next, w;
	};//C++ struct is already a type

	bool neg_cycle;
	int checked_start;

	int Vnum, Enum;
	vector< vector<EDGE> > edge;
	vector<int> prev;
	vector<ll> dis;

	void SPFA(int start)
	{
		int i;
		int nowv, nextv, siz;
		queue<int> check;
		vector<int> count(Vnum+1);
		vector<bool> inqueue(Vnum+1);

		checked_start = start;

		fill(prev.begin(), prev.begin()+Vnum+1, -1);
		fill(dis.begin(), dis.begin()+Vnum+1, INF);

		fill(inqueue.begin(), inqueue.begin()+Vnum, false);
		fill(count.begin(), count.begin()+Vnum, 0);

		dis[start] = 0;
		check.push(start);
		inqueue[start] = true;
		count[start]++;

		while(!check.empty()){
			nowv = check.front();
			check.pop();
			inqueue[nowv] = false;
			siz = edge[nowv].size();
			for(i=0;i<siz;i++){
				nextv = edge[nowv][i].next;
				if(dis[nextv] > dis[nowv] + edge[nowv][i].w){
					dis[nextv] = dis[nowv] + edge[nowv][i].w;
					prev[nextv] = nowv;
					if(!inqueue[nextv]){
						check.push(nextv);
						inqueue[nextv] = true;
						count[nextv]++;
						if(count[nextv] >= Vnum ){

							neg_cycle = true;

							return ;
						}
					}
				}
			}
		}

		neg_cycle = false;
	}
};


ll D[55555];
vector<pair<ii,ii> > edges;
int n,m; 
ll res=ll(1e18);
ll adj[222][222];

void test(int id)
{
	Graph G(n);
	LIB_SPFA sG(n);
	for(int i=0;i<n;i++)
	{
		for(int j=0;j<n;j++)
		{
			adj[i][j]=ll(1e18);
			if(i==j) adj[i][j]=0;
		}
	}
	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);
		adj[u][v]=min(adj[u][v],edges[i].se.fi);
	}
	for(int i=0;i<n;i++)
	{
		for(int j=0;j<n;j++)
		{
			if(i!=j&&adj[i][j]<ll(1e18)) sG.add_edge(i,j,adj[i][j]);
			//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];
	ll ans = sG.get_dis(0,n-1)+sG.get_dis(n-1,0);
	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({c+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];
	sort(VV.begin(),VV.end());
	for(int i=0;i<min(100,m);i++) S.insert(VV[i].se);
	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:144:21: 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:311:6: 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 71 ms 1400 KB Output is correct
2 Correct 37 ms 1144 KB Output is correct
3 Correct 86 ms 1400 KB Output is correct
4 Correct 89 ms 1528 KB Output is correct
5 Correct 12 ms 760 KB Output is correct
6 Correct 35 ms 1144 KB Output is correct
7 Correct 5 ms 376 KB Output is correct
8 Correct 5 ms 376 KB Output is correct
9 Correct 5 ms 504 KB Output is correct
10 Correct 75 ms 1400 KB Output is correct
11 Correct 86 ms 1528 KB Output is correct
12 Correct 84 ms 1452 KB Output is correct
13 Correct 71 ms 1400 KB Output is correct
14 Correct 82 ms 1400 KB Output is correct
15 Correct 82 ms 1272 KB Output is correct
16 Correct 85 ms 1528 KB Output is correct

Subtask #2
11.0 / 11.0

# Verdict Execution time Memory Grader output
1 Correct 80 ms 12376 KB Output is correct
2 Correct 86 ms 12376 KB Output is correct
3 Correct 79 ms 12116 KB Output is correct
4 Correct 16 ms 1272 KB Output is correct
5 Correct 15 ms 1020 KB Output is correct
6 Correct 15 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 87 ms 12504 KB Output is correct
10 Correct 81 ms 12752 KB Output is correct
11 Correct 81 ms 12252 KB Output is correct
12 Correct 85 ms 12504 KB Output is correct
13 Correct 78 ms 12376 KB Output is correct
14 Correct 80 ms 13768 KB Output is correct

Subtask #3
21.0 / 21.0

# Verdict Execution time Memory Grader output
1 Correct 66 ms 1400 KB Output is correct
2 Correct 38 ms 1144 KB Output is correct
3 Correct 528 ms 11484 KB Output is correct
4 Correct 45 ms 1144 KB Output is correct
5 Correct 588 ms 13788 KB Output is correct
6 Correct 4 ms 376 KB Output is correct
7 Correct 5 ms 376 KB Output is correct
8 Correct 542 ms 13656 KB Output is correct
9 Correct 528 ms 13520 KB Output is correct
10 Correct 493 ms 12760 KB Output is correct
11 Correct 488 ms 12764 KB Output is correct
12 Correct 515 ms 13520 KB Output is correct
13 Correct 5 ms 376 KB Output is correct
14 Correct 5 ms 376 KB Output is correct
15 Correct 4 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 501 ms 13408 KB Output is correct
20 Correct 515 ms 12884 KB Output is correct
21 Correct 512 ms 13016 KB Output is correct
22 Correct 491 ms 12632 KB Output is correct

Subtask #4
0 / 63.0

# Verdict Execution time Memory Grader output
1 Correct 71 ms 1400 KB Output is correct
2 Correct 37 ms 1144 KB Output is correct
3 Correct 86 ms 1400 KB Output is correct
4 Correct 89 ms 1528 KB Output is correct
5 Correct 12 ms 760 KB Output is correct
6 Correct 35 ms 1144 KB Output is correct
7 Correct 5 ms 376 KB Output is correct
8 Correct 5 ms 376 KB Output is correct
9 Correct 5 ms 504 KB Output is correct
10 Correct 75 ms 1400 KB Output is correct
11 Correct 86 ms 1528 KB Output is correct
12 Correct 84 ms 1452 KB Output is correct
13 Correct 71 ms 1400 KB Output is correct
14 Correct 82 ms 1400 KB Output is correct
15 Correct 82 ms 1272 KB Output is correct
16 Correct 85 ms 1528 KB Output is correct
17 Correct 80 ms 12376 KB Output is correct
18 Correct 86 ms 12376 KB Output is correct
19 Correct 79 ms 12116 KB Output is correct
20 Correct 16 ms 1272 KB Output is correct
21 Correct 15 ms 1020 KB Output is correct
22 Correct 15 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 87 ms 12504 KB Output is correct
26 Correct 81 ms 12752 KB Output is correct
27 Correct 81 ms 12252 KB Output is correct
28 Correct 85 ms 12504 KB Output is correct
29 Correct 78 ms 12376 KB Output is correct
30 Correct 80 ms 13768 KB Output is correct
31 Correct 66 ms 1400 KB Output is correct
32 Correct 38 ms 1144 KB Output is correct
33 Correct 528 ms 11484 KB Output is correct
34 Correct 45 ms 1144 KB Output is correct
35 Correct 588 ms 13788 KB Output is correct
36 Correct 4 ms 376 KB Output is correct
37 Correct 5 ms 376 KB Output is correct
38 Correct 542 ms 13656 KB Output is correct
39 Correct 528 ms 13520 KB Output is correct
40 Correct 493 ms 12760 KB Output is correct
41 Correct 488 ms 12764 KB Output is correct
42 Correct 515 ms 13520 KB Output is correct
43 Correct 5 ms 376 KB Output is correct
44 Correct 5 ms 376 KB Output is correct
45 Correct 4 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 501 ms 13408 KB Output is correct
50 Correct 515 ms 12884 KB Output is correct
51 Correct 512 ms 13016 KB Output is correct
52 Correct 491 ms 12632 KB Output is correct
53 Correct 767 ms 13704 KB Output is correct
54 Correct 788 ms 13676 KB Output is correct
55 Correct 732 ms 13632 KB Output is correct
56 Correct 89 ms 1400 KB Output is correct
57 Correct 82 ms 1400 KB Output is correct
58 Correct 687 ms 11736 KB Output is correct
59 Correct 713 ms 11632 KB Output is correct
60 Correct 828 ms 11604 KB Output is correct
61 Correct 648 ms 11616 KB Output is correct
62 Correct 624 ms 11608 KB Output is correct
63 Correct 753 ms 11684 KB Output is correct
64 Execution timed out 1088 ms 11352 KB Time limit exceeded
65 Halted 0 ms 0 KB -