oj.uz

Submission #778081

# Submission time Handle Problem Language Result Execution time Memory
778081 2023-07-10T05:59:34 Z CSQ31 Simurgh (IOI17_simurgh) C++17
30 / 100
 3000 ms 11864 KB 
#include "simurgh.h"
#include<bits/stdc++.h>
using namespace std;
#define pb push_back
#define fi first
#define se second
#define sz(a) (int)(a.size())
#define all(a) a.begin(),a.end()
typedef long long int ll;
typedef pair<int,int> pii;
const int MAXN = 2e5;
int par[MAXN],szz[MAXN],good[MAXN],tree[MAXN];
vector<pii>adj[MAXN],ed;
int find(int x){
	if(x==par[x])return x;
	return par[x] = find(par[x]);
}
bool unite(int a,int b){
	a = find(a);
	b = find(b);
	if(a==b)return 0;
	if(szz[a] > szz[b])swap(a,b);
	par[a] = b;
	szz[b]+=szz[a];
	return 1;
}
void init(int n){
	for(int i=0;i<n;i++){
		par[i] = i;
		szz[i] = 1;
	}
}
set<int>edges;
vector<int>edge;
int nn;
bool debug = 1;
int ask(){
	vector<int>r;
	if(edges.empty())for(int x:edge)r.pb(x);
	else for(int x:edges)r.pb(x);
	if(debug)assert(sz(r)==nn-1);
	return count_common_roads(r);
}

pii p[MAXN];
int dep[MAXN],vis[MAXN],glob;
void dfs(int v,int u){
	vis[v] = 1;
	for(pii z:adj[v]){
		int x = z.fi;
		int id = z.se;
		if(vis[x] || x==u)continue;
		tree[id] = 1;
		edges.insert(id);
		dep[x] = dep[v]+1;
		p[x] = {v,id};
		dfs(x,v);
	}
}
void dfs2(int v,int u){
	
	for(pii z:adj[v]){
		int x = z.fi;
		int id = z.se;
		if(tree[id]){
			if(x!=u)dfs2(x,v);
			continue;
		}
		if(dep[x] > dep[v])continue; //go downwards
		
		vector<int>path,res;
		int cur = v;
		while(cur != x){
			path.pb(p[cur].se);
			cur = p[cur].fi;
		}
		//for(int e:path)cout<<e<<" ";
		//cout<<'\n';
		int have = 0;
		for(int e:path)have += (good[e] == -1);
		if(!have)continue; //if all tree edge part of this cycle is known,skip
		edges.insert(id);
		if(have == sz(path)){ //everything is unknown
			//cout<<"case 1"<<'\n';
			for(int e:path){
				edges.erase(e);
				res.pb(ask());
				edges.insert(e);
			}
			path.pb(id);
			res.pb(glob);
			int s = sz(path);
			for(int i=0;i<s;i++){
				int j = (i+s-1) % s;
				if(res[i] == res[j])continue;
				good[path[i]] = 1;
				good[path[j]] = 0;
				if(res[i] > res[j])swap(good[path[i]],good[path[j]]);
			}
			for(int i=0;i<s;i++){
				int j = (i+s-1) % s;
				if(good[path[j]] >= 0 && res[i] == res[j])good[path[i]] = good[path[j]];
			}
			for(int i=s-1;i>=0;i--){
				int j = (i+1) % s;
				if(good[path[j]] >= 0 && res[i] == res[j])good[path[i]] = good[path[j]];
			}
		}else{
			//cout<<"case 2"<<'\n';
			if(good[id] == -1){
				for(int e:path){
					if(good[e] == -1)continue;
					edges.erase(e);
					int res2 = ask();
					edges.insert(e);
					if(res2 == glob)good[id] = good[e];
					else if(res2 > glob)good[id] = 1; 
					else good[id] = 0;
					break;
				}
			}
			//cout<<good[id]<<'\n';
			for(int e:path){
				if(good[e] != -1)continue;
				edges.erase(e);
				int res2 = ask();
				edges.insert(e);
				if(res2 == glob)good[e] = good[id];
				else if(res2 > glob)good[e] = 0;
				else good[e] = 1;
			}
		}
		edges.erase(id);
	}
}

vector<int>e,solved;
void solve(int l,int r,int n){
	if(l>r)return;
	init(n);
	edge.clear();
	for(int i=l;i<=r;i++){
		if(unite(ed[e[i]].fi,ed[e[i]].se))edge.pb(e[i]);
	}
	int tot = 0;
	
	for(int i=0;i<sz(ed);i++){
		if(good[i]>=0){
			if(unite(ed[i].fi,ed[i].se)){
				edge.pb(i);
				tot+=good[i];
			}
			
		}
		
	}
	int res = ask();
	edge.clear();
	if(res == tot){
		for(int i=l;i<=r;i++)good[e[i]] = 0;
		return;
	}else if(res == tot + r-l+1){
		for(int i=l;i<=r;i++)good[e[i]] = 1;
		return;
	}
	int mid = (l+r)/2;
	solve(l,mid,n);
	solve(mid+1,r,n);
	
	
}
vector<int> find_roads(int N,vector<int> u,vector<int> v) {
	nn = N;
	int n = N;
	int m = sz(u);
	for(int i=0;i<m;i++)ed.pb({v[i],u[i]});
	for(int i=0;i<m;i++){
		good[i] = -1;
		adj[u[i]].pb({v[i],i});
		adj[v[i]].pb({u[i],i});
	}
	dfs(0,-1);
	glob = ask();
	dfs2(0,-1);
	debug = 0;
	//for(int i=0;i<m;i++)cout<<good[i]<<" ";
	//cout<<'\n';
	for(int x:edges){
		if(good[x]==-1)good[x] = 1; //this is a bridge
		
		
	}
	int cnt = m;
	for(int i=0;i<m;i++){
		//cout<<good[i]<<" ";
		if(good[i]>=0){
			cnt--;
			solved.pb(i);
		}
	}
	edges.clear();
	while(cnt){
		init(n);
		e.clear();
		for(int i=0;i<m;i++){
			if(good[i] >= 0)continue;
			if(unite(v[i],u[i]))e.pb(i);
		}
		cnt-=sz(e);
		solve(0,sz(e)-1,n);
		for(int x:e)solved.pb(x);
	}
	vector<int>ans;
	for(int i=0;i<m;i++){
		if(good[i] == 1)ans.pb(i);
	}
	return ans;
}

Subtask #1
13.0 / 13.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 4948 KB correct
2 Correct 2 ms 4948 KB correct
3 Correct 2 ms 4948 KB correct
4 Correct 3 ms 4948 KB correct
5 Correct 2 ms 4948 KB correct
6 Correct 2 ms 4948 KB correct
7 Correct 2 ms 4948 KB correct
8 Correct 2 ms 4948 KB correct
9 Correct 2 ms 4948 KB correct
10 Correct 2 ms 4948 KB correct
11 Correct 3 ms 4948 KB correct
12 Correct 3 ms 4948 KB correct
13 Correct 2 ms 4948 KB correct

Subtask #2
17.0 / 17.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 4948 KB correct
2 Correct 2 ms 4948 KB correct
3 Correct 2 ms 4948 KB correct
4 Correct 3 ms 4948 KB correct
5 Correct 2 ms 4948 KB correct
6 Correct 2 ms 4948 KB correct
7 Correct 2 ms 4948 KB correct
8 Correct 2 ms 4948 KB correct
9 Correct 2 ms 4948 KB correct
10 Correct 2 ms 4948 KB correct
11 Correct 3 ms 4948 KB correct
12 Correct 3 ms 4948 KB correct
13 Correct 2 ms 4948 KB correct
14 Correct 6 ms 5132 KB correct
15 Correct 5 ms 5076 KB correct
16 Correct 6 ms 5124 KB correct
17 Correct 5 ms 5076 KB correct
18 Correct 3 ms 5076 KB correct
19 Correct 5 ms 5112 KB correct
20 Correct 5 ms 5020 KB correct
21 Correct 5 ms 5076 KB correct
22 Correct 3 ms 5076 KB correct
23 Correct 3 ms 5076 KB correct
24 Correct 3 ms 5076 KB correct
25 Correct 3 ms 5012 KB correct
26 Correct 3 ms 5016 KB correct
27 Correct 3 ms 5076 KB correct
28 Correct 3 ms 5076 KB correct
29 Correct 3 ms 4948 KB correct
30 Correct 3 ms 5076 KB correct
31 Correct 3 ms 5076 KB correct
32 Correct 3 ms 5076 KB correct
33 Correct 3 ms 5076 KB correct

Subtask #3
0 / 21.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 4948 KB correct
2 Correct 2 ms 4948 KB correct
3 Correct 2 ms 4948 KB correct
4 Correct 3 ms 4948 KB correct
5 Correct 2 ms 4948 KB correct
6 Correct 2 ms 4948 KB correct
7 Correct 2 ms 4948 KB correct
8 Correct 2 ms 4948 KB correct
9 Correct 2 ms 4948 KB correct
10 Correct 2 ms 4948 KB correct
11 Correct 3 ms 4948 KB correct
12 Correct 3 ms 4948 KB correct
13 Correct 2 ms 4948 KB correct
14 Correct 6 ms 5132 KB correct
15 Correct 5 ms 5076 KB correct
16 Correct 6 ms 5124 KB correct
17 Correct 5 ms 5076 KB correct
18 Correct 3 ms 5076 KB correct
19 Correct 5 ms 5112 KB correct
20 Correct 5 ms 5020 KB correct
21 Correct 5 ms 5076 KB correct
22 Correct 3 ms 5076 KB correct
23 Correct 3 ms 5076 KB correct
24 Correct 3 ms 5076 KB correct
25 Correct 3 ms 5012 KB correct
26 Correct 3 ms 5016 KB correct
27 Correct 3 ms 5076 KB correct
28 Correct 3 ms 5076 KB correct
29 Correct 3 ms 4948 KB correct
30 Correct 3 ms 5076 KB correct
31 Correct 3 ms 5076 KB correct
32 Correct 3 ms 5076 KB correct
33 Correct 3 ms 5076 KB correct
34 Correct 364 ms 6912 KB correct
35 Correct 347 ms 6888 KB correct
36 Correct 258 ms 6556 KB correct
37 Correct 14 ms 5076 KB correct
38 Correct 358 ms 6956 KB correct
39 Correct 298 ms 6672 KB correct
40 Correct 246 ms 6516 KB correct
41 Incorrect 110 ms 6664 KB WA in grader: NO
42 Halted 0 ms 0 KB -

Subtask #4
0 / 19.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 4948 KB correct
2 Correct 3 ms 4948 KB correct
3 Correct 1829 ms 9916 KB correct
4 Execution timed out 3072 ms 11864 KB Time limit exceeded
5 Halted 0 ms 0 KB -

Subtask #5
0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 4948 KB correct
2 Correct 2 ms 4948 KB correct
3 Correct 2 ms 4948 KB correct
4 Correct 3 ms 4948 KB correct
5 Correct 2 ms 4948 KB correct
6 Correct 2 ms 4948 KB correct
7 Correct 2 ms 4948 KB correct
8 Correct 2 ms 4948 KB correct
9 Correct 2 ms 4948 KB correct
10 Correct 2 ms 4948 KB correct
11 Correct 3 ms 4948 KB correct
12 Correct 3 ms 4948 KB correct
13 Correct 2 ms 4948 KB correct
14 Correct 6 ms 5132 KB correct
15 Correct 5 ms 5076 KB correct
16 Correct 6 ms 5124 KB correct
17 Correct 5 ms 5076 KB correct
18 Correct 3 ms 5076 KB correct
19 Correct 5 ms 5112 KB correct
20 Correct 5 ms 5020 KB correct
21 Correct 5 ms 5076 KB correct
22 Correct 3 ms 5076 KB correct
23 Correct 3 ms 5076 KB correct
24 Correct 3 ms 5076 KB correct
25 Correct 3 ms 5012 KB correct
26 Correct 3 ms 5016 KB correct
27 Correct 3 ms 5076 KB correct
28 Correct 3 ms 5076 KB correct
29 Correct 3 ms 4948 KB correct
30 Correct 3 ms 5076 KB correct
31 Correct 3 ms 5076 KB correct
32 Correct 3 ms 5076 KB correct
33 Correct 3 ms 5076 KB correct
34 Correct 364 ms 6912 KB correct
35 Correct 347 ms 6888 KB correct
36 Correct 258 ms 6556 KB correct
37 Correct 14 ms 5076 KB correct
38 Correct 358 ms 6956 KB correct
39 Correct 298 ms 6672 KB correct
40 Correct 246 ms 6516 KB correct
41 Incorrect 110 ms 6664 KB WA in grader: NO
42 Halted 0 ms 0 KB -