oj.uz

Submission #68686

# Submission time Handle Problem Language Result Execution time Memory
68686 2018-08-18T05:20:22 Z zscoder Simurgh (IOI17_simurgh) C++17
51 / 100
 165 ms 6892 KB 
#include "simurgh.h"
#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
 
typedef long long ll;
typedef pair<int,int> ii;
typedef vector<int> vi;
typedef long double ld; 
typedef tree<ii, null_type, less<ii>, rb_tree_tag, tree_order_statistics_node_update> pbds;

struct edge
{
	int to, id;
	edge(int _to, int _id) : to(_to),id(_id){}
};

vector<edge> adj[555];
int timer;
int in[555];
int royal[555555];
int par[555];
int paredge[555];
bool vis[555];
int backedge[555];
int low[555];
vector<int> S;

void prep(int u=0, int p=-1)
{
	in[u]=timer++; par[u]=p; vis[u]=1; low[u]=in[u];
	for(auto X:adj[u])
	{
		int v=X.to; int lab=X.id;
		if(v==p) continue;
		if(vis[v])
		{
			if(in[v]<low[u])
			{
				low[u]=in[v];
				backedge[u]=lab;
			}
		}
		else
		{
			S.pb(lab); paredge[v]=lab;
			//cerr<<"TREE EDGE "<<u<<' '<<v<<'\n';
			prep(v,u);
			if(low[v]<low[u])
			{
				low[u]=low[v];
				backedge[u]=backedge[v];
			}
		}
	}
}

int query(int u, int v) //del edge u, add edge v
{
	vi V;
	for(int x:S)
	{
		if(x!=u) V.pb(x);
	}
	V.pb(v);
	/*
	cerr<<"QUERY\n";
	for(int v:V)
	{
		cerr<<v<<' ';
	}
	cerr<<'\n';
	*/
	return count_common_roads(V);
}

std::vector<int> find_roads(int n, std::vector<int> u, std::vector<int> v) 
{
	vi ans; int m=u.size();
	for(int i=0;i<m;i++) 
	{
		adj[u[i]].pb(edge(v[i],i)); adj[v[i]].pb(edge(u[i],i));
	}
	for(int i=0;i<n;i++) backedge[i]=-1;
	prep();
	for(int i=0;i<m;i++) royal[i]=-1;
	int tree_common = count_common_roads(S);
	vi backedges;
	for(int i=0;i<n;i++)
	{
		if(backedge[i]!=-1)
		{
			int x=u[backedge[i]]; int y=v[backedge[i]];
			if(in[x]<in[y]) swap(x,y);
			//cerr<<"BACK EDGE "<<i<<' '<<x<<' '<<y<<'\n';
			//x is grandchild of y
			vi path;
			while(x!=y)
			{
				path.pb(paredge[x]); x=par[x];
			}
			int known=-1;
			for(int e:path)
			{
				if(royal[e]!=-1) 
				{
					known=e;
					break;
				}
			}
			if(known==-1) //if no known edge, do the entire cycle
			{
				vi arr(int(path.size()));
				
				int exnonzero=-1;
				for(int j=0;j<path.size();j++)
				{
					arr[j]=query(path[j],backedge[i])-tree_common;
					if(arr[j]!=0) exnonzero=j;
				}
				
				//all 0 => none of them is part of tree because it's a cycle
				if(exnonzero==-1)
				{
					for(int v:path) royal[v]=0;
					royal[backedge[i]]=0;
				}
				else
				{
					if(arr[exnonzero]==1) //meaning backedge[i] is good
					{
						royal[backedge[i]]=1;
						for(int i=0;i<path.size();i++)
						{
							if(arr[i]==1) royal[path[i]]=0;
							else royal[path[i]]=1;
						}
					}
					else
					{
						royal[backedge[i]]=0;
						for(int i=0;i<path.size();i++)
						{
							if(arr[i]==0) royal[path[i]]=0;
							else royal[path[i]]=1;
						}
					}
				}
				/*
				cerr<<"RESULT : \n";
				for(int v:path) cerr<<v<<' '<<royal[v]<<'\n';
				cerr<<backedge[i]<<' '<<royal[backedge[i]]<<'\n';
				cerr<<'\n';
				*/
			}
			else //known is a known tree edge
			{
				int v = query(known, backedge[i]) - tree_common;
				v+=royal[known]; royal[backedge[i]]=v;
				for(int e:path)
				{
					if(royal[e]==-1)
					{
						int val = tree_common-query(e,backedge[i]);
						val+=royal[backedge[i]];
						royal[e]=val;
					}
				}
				/*
				cerr<<"RESULT : \n";
				for(int v:path) cerr<<v<<' '<<royal[v]<<'\n';
				cerr<<backedge[i]<<' '<<royal[backedge[i]]<<'\n';
				cerr<<'\n';
				*/
			}
		}
	}
	for(int e:S)
	{
		if(royal[e]==-1) royal[e]=1; //because it is a bridge
	}
	//now we should have determined the affinity of all the tree edges
	for(int i=0;i<m;i++)
	{
		if(royal[i]==-1)
		{
			int x=u[i]; int y=v[i];
			if(in[x]<in[y]) swap(x,y);
			//x is a grandchild of y
			int v = query(paredge[x], i) - tree_common;
			v+=royal[paredge[x]];
			royal[i]=v;
		}
	}
	for(int i=0;i<m;i++)
	{
		if(royal[i]) ans.pb(i);
	}
	return ans;
}

Compilation message

simurgh.cpp: In function 'std::vector<int> find_roads(int, std::vector<int>, std::vector<int>)':
simurgh.cpp:124:18: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     for(int j=0;j<path.size();j++)
                 ~^~~~~~~~~~~~
simurgh.cpp:141:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
       for(int i=0;i<path.size();i++)
                   ~^~~~~~~~~~~~
simurgh.cpp:150:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
       for(int i=0;i<path.size();i++)
                   ~^~~~~~~~~~~~

Subtask #1
13.0 / 13.0

# Verdict Execution time Memory Grader output
1 Correct 3 ms 376 KB correct
2 Correct 2 ms 376 KB correct
3 Correct 2 ms 432 KB correct
4 Correct 3 ms 508 KB correct
5 Correct 2 ms 544 KB correct
6 Correct 2 ms 544 KB correct
7 Correct 3 ms 544 KB correct
8 Correct 2 ms 544 KB correct
9 Correct 2 ms 544 KB correct
10 Correct 2 ms 544 KB correct
11 Correct 3 ms 544 KB correct
12 Correct 3 ms 544 KB correct
13 Correct 2 ms 548 KB correct

Subtask #2
17.0 / 17.0

# Verdict Execution time Memory Grader output
1 Correct 3 ms 376 KB correct
2 Correct 2 ms 376 KB correct
3 Correct 2 ms 432 KB correct
4 Correct 3 ms 508 KB correct
5 Correct 2 ms 544 KB correct
6 Correct 2 ms 544 KB correct
7 Correct 3 ms 544 KB correct
8 Correct 2 ms 544 KB correct
9 Correct 2 ms 544 KB correct
10 Correct 2 ms 544 KB correct
11 Correct 3 ms 544 KB correct
12 Correct 3 ms 544 KB correct
13 Correct 2 ms 548 KB correct
14 Correct 4 ms 548 KB correct
15 Correct 7 ms 548 KB correct
16 Correct 5 ms 584 KB correct
17 Correct 5 ms 640 KB correct
18 Correct 3 ms 640 KB correct
19 Correct 6 ms 640 KB correct
20 Correct 6 ms 644 KB correct
21 Correct 4 ms 832 KB correct
22 Correct 4 ms 832 KB correct
23 Correct 4 ms 832 KB correct
24 Correct 4 ms 832 KB correct
25 Correct 3 ms 832 KB correct
26 Correct 4 ms 832 KB correct
27 Correct 4 ms 832 KB correct
28 Correct 4 ms 832 KB correct
29 Correct 3 ms 832 KB correct
30 Correct 3 ms 836 KB correct
31 Correct 4 ms 840 KB correct
32 Correct 4 ms 844 KB correct
33 Correct 5 ms 856 KB correct

Subtask #3
21.0 / 21.0

# Verdict Execution time Memory Grader output
1 Correct 3 ms 376 KB correct
2 Correct 2 ms 376 KB correct
3 Correct 2 ms 432 KB correct
4 Correct 3 ms 508 KB correct
5 Correct 2 ms 544 KB correct
6 Correct 2 ms 544 KB correct
7 Correct 3 ms 544 KB correct
8 Correct 2 ms 544 KB correct
9 Correct 2 ms 544 KB correct
10 Correct 2 ms 544 KB correct
11 Correct 3 ms 544 KB correct
12 Correct 3 ms 544 KB correct
13 Correct 2 ms 548 KB correct
14 Correct 4 ms 548 KB correct
15 Correct 7 ms 548 KB correct
16 Correct 5 ms 584 KB correct
17 Correct 5 ms 640 KB correct
18 Correct 3 ms 640 KB correct
19 Correct 6 ms 640 KB correct
20 Correct 6 ms 644 KB correct
21 Correct 4 ms 832 KB correct
22 Correct 4 ms 832 KB correct
23 Correct 4 ms 832 KB correct
24 Correct 4 ms 832 KB correct
25 Correct 3 ms 832 KB correct
26 Correct 4 ms 832 KB correct
27 Correct 4 ms 832 KB correct
28 Correct 4 ms 832 KB correct
29 Correct 3 ms 832 KB correct
30 Correct 3 ms 836 KB correct
31 Correct 4 ms 840 KB correct
32 Correct 4 ms 844 KB correct
33 Correct 5 ms 856 KB correct
34 Correct 165 ms 2136 KB correct
35 Correct 161 ms 2240 KB correct
36 Correct 111 ms 2276 KB correct
37 Correct 11 ms 2276 KB correct
38 Correct 152 ms 2696 KB correct
39 Correct 134 ms 2812 KB correct
40 Correct 117 ms 2812 KB correct
41 Correct 156 ms 3204 KB correct
42 Correct 147 ms 3408 KB correct
43 Correct 84 ms 3408 KB correct
44 Correct 64 ms 3408 KB correct
45 Correct 80 ms 3408 KB correct
46 Correct 54 ms 3408 KB correct
47 Correct 28 ms 3408 KB correct
48 Correct 5 ms 3408 KB correct
49 Correct 14 ms 3408 KB correct
50 Correct 28 ms 3408 KB correct
51 Correct 78 ms 3440 KB correct
52 Correct 59 ms 3496 KB correct
53 Correct 59 ms 3500 KB correct
54 Correct 87 ms 3832 KB correct
55 Correct 76 ms 3832 KB correct
56 Correct 82 ms 3988 KB correct
57 Correct 74 ms 4036 KB correct

Subtask #4
0 / 19.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 4036 KB correct
2 Correct 2 ms 4036 KB correct
3 Incorrect 142 ms 6892 KB WA in grader: NO
4 Halted 0 ms 0 KB -

Subtask #5
0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 3 ms 376 KB correct
2 Correct 2 ms 376 KB correct
3 Correct 2 ms 432 KB correct
4 Correct 3 ms 508 KB correct
5 Correct 2 ms 544 KB correct
6 Correct 2 ms 544 KB correct
7 Correct 3 ms 544 KB correct
8 Correct 2 ms 544 KB correct
9 Correct 2 ms 544 KB correct
10 Correct 2 ms 544 KB correct
11 Correct 3 ms 544 KB correct
12 Correct 3 ms 544 KB correct
13 Correct 2 ms 548 KB correct
14 Correct 4 ms 548 KB correct
15 Correct 7 ms 548 KB correct
16 Correct 5 ms 584 KB correct
17 Correct 5 ms 640 KB correct
18 Correct 3 ms 640 KB correct
19 Correct 6 ms 640 KB correct
20 Correct 6 ms 644 KB correct
21 Correct 4 ms 832 KB correct
22 Correct 4 ms 832 KB correct
23 Correct 4 ms 832 KB correct
24 Correct 4 ms 832 KB correct
25 Correct 3 ms 832 KB correct
26 Correct 4 ms 832 KB correct
27 Correct 4 ms 832 KB correct
28 Correct 4 ms 832 KB correct
29 Correct 3 ms 832 KB correct
30 Correct 3 ms 836 KB correct
31 Correct 4 ms 840 KB correct
32 Correct 4 ms 844 KB correct
33 Correct 5 ms 856 KB correct
34 Correct 165 ms 2136 KB correct
35 Correct 161 ms 2240 KB correct
36 Correct 111 ms 2276 KB correct
37 Correct 11 ms 2276 KB correct
38 Correct 152 ms 2696 KB correct
39 Correct 134 ms 2812 KB correct
40 Correct 117 ms 2812 KB correct
41 Correct 156 ms 3204 KB correct
42 Correct 147 ms 3408 KB correct
43 Correct 84 ms 3408 KB correct
44 Correct 64 ms 3408 KB correct
45 Correct 80 ms 3408 KB correct
46 Correct 54 ms 3408 KB correct
47 Correct 28 ms 3408 KB correct
48 Correct 5 ms 3408 KB correct
49 Correct 14 ms 3408 KB correct
50 Correct 28 ms 3408 KB correct
51 Correct 78 ms 3440 KB correct
52 Correct 59 ms 3496 KB correct
53 Correct 59 ms 3500 KB correct
54 Correct 87 ms 3832 KB correct
55 Correct 76 ms 3832 KB correct
56 Correct 82 ms 3988 KB correct
57 Correct 74 ms 4036 KB correct
58 Correct 2 ms 4036 KB correct
59 Correct 2 ms 4036 KB correct
60 Incorrect 142 ms 6892 KB WA in grader: NO
61 Halted 0 ms 0 KB -