Submission #778212

# Submission time Handle Problem Language Result Execution time Memory
778212 2023-07-10T07:28:16 Z CSQ31 Simurgh (IOI17_simurgh) C++17
51 / 100
250 ms 24912 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 = 0;
int Q = 0;
int ask(){
	Q++;
	if(nn==500)assert(Q<=8000);
	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]];
			}
			for(int x:path){
				if(good[x] == -1)good[x] = 0;
			}
		}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){
	if(l>r)return;
	init(nn);
	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:solved){
		if(unite(ed[i].fi,ed[i].se)){
			edge.pb(i);
			tot+=good[i];
		}
		if(sz(edge)==nn-1)break;
		
	}
	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);
	solve(mid+1,r);
	
	
}
mt19937 seed(chrono::high_resolution_clock::now().time_since_epoch().count());
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;
	//2n queries here at most = 1000
	int found = 0;
	for(int x:edges){
		if(good[x]==-1)good[x] = 1; //this is a bridge	
	}
	for(int i=0;i<m;i++){
		//cout<<good[i]<<" ";
		if(good[i]>=0){
			found++;
			solved.pb(i);
		}
	}
	edges.clear();
	for(int i=0;i<n;i++){
		e.clear();
		for(pii x:adj[i]){
			if(good[x.se] == -1)e.pb(x.se);
		}
		if(e.empty())continue;
		solve(0,sz(e)-1);
		for(int x:e){
			found+=good[x];
			solved.pb(x);
		}
		
	}
	vector<int>ans;
	for(int i=0;i<m;i++){
		if(good[i] == 1)ans.pb(i);
	}
	return ans;
}
# Verdict Execution time Memory Grader output
1 Correct 3 ms 4948 KB correct
2 Correct 2 ms 4948 KB correct
3 Correct 2 ms 5012 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 4 ms 5084 KB correct
8 Correct 3 ms 4948 KB correct
9 Correct 2 ms 4948 KB correct
10 Correct 3 ms 4956 KB correct
11 Correct 2 ms 4948 KB correct
12 Correct 3 ms 5012 KB correct
13 Correct 3 ms 4948 KB correct
# Verdict Execution time Memory Grader output
1 Correct 3 ms 4948 KB correct
2 Correct 2 ms 4948 KB correct
3 Correct 2 ms 5012 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 4 ms 5084 KB correct
8 Correct 3 ms 4948 KB correct
9 Correct 2 ms 4948 KB correct
10 Correct 3 ms 4956 KB correct
11 Correct 2 ms 4948 KB correct
12 Correct 3 ms 5012 KB correct
13 Correct 3 ms 4948 KB correct
14 Correct 4 ms 5148 KB correct
15 Correct 3 ms 5076 KB correct
16 Correct 4 ms 5020 KB correct
17 Correct 4 ms 5024 KB correct
18 Correct 3 ms 5076 KB correct
19 Correct 4 ms 5016 KB correct
20 Correct 4 ms 5076 KB correct
21 Correct 4 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 5016 KB correct
26 Correct 4 ms 5012 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 5032 KB correct
31 Correct 4 ms 5076 KB correct
32 Correct 3 ms 5076 KB correct
33 Correct 3 ms 5012 KB correct
# Verdict Execution time Memory Grader output
1 Correct 3 ms 4948 KB correct
2 Correct 2 ms 4948 KB correct
3 Correct 2 ms 5012 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 4 ms 5084 KB correct
8 Correct 3 ms 4948 KB correct
9 Correct 2 ms 4948 KB correct
10 Correct 3 ms 4956 KB correct
11 Correct 2 ms 4948 KB correct
12 Correct 3 ms 5012 KB correct
13 Correct 3 ms 4948 KB correct
14 Correct 4 ms 5148 KB correct
15 Correct 3 ms 5076 KB correct
16 Correct 4 ms 5020 KB correct
17 Correct 4 ms 5024 KB correct
18 Correct 3 ms 5076 KB correct
19 Correct 4 ms 5016 KB correct
20 Correct 4 ms 5076 KB correct
21 Correct 4 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 5016 KB correct
26 Correct 4 ms 5012 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 5032 KB correct
31 Correct 4 ms 5076 KB correct
32 Correct 3 ms 5076 KB correct
33 Correct 3 ms 5012 KB correct
34 Correct 54 ms 6896 KB correct
35 Correct 48 ms 6824 KB correct
36 Correct 41 ms 6452 KB correct
37 Correct 9 ms 5076 KB correct
38 Correct 55 ms 6904 KB correct
39 Correct 40 ms 6664 KB correct
40 Correct 35 ms 6548 KB correct
41 Correct 46 ms 6856 KB correct
42 Correct 47 ms 6900 KB correct
43 Correct 16 ms 6228 KB correct
44 Correct 14 ms 5900 KB correct
45 Correct 16 ms 5916 KB correct
46 Correct 13 ms 5844 KB correct
47 Correct 9 ms 5476 KB correct
48 Correct 4 ms 5016 KB correct
49 Correct 6 ms 5276 KB correct
50 Correct 8 ms 5460 KB correct
51 Correct 15 ms 5972 KB correct
52 Correct 16 ms 5912 KB correct
53 Correct 12 ms 5812 KB correct
54 Correct 16 ms 6228 KB correct
55 Correct 17 ms 5972 KB correct
56 Correct 17 ms 5972 KB correct
57 Correct 18 ms 5972 KB correct
# Verdict Execution time Memory Grader output
1 Correct 3 ms 4948 KB correct
2 Correct 2 ms 4948 KB correct
3 Correct 153 ms 10676 KB correct
4 Runtime error 250 ms 24912 KB Execution killed with signal 6
5 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 3 ms 4948 KB correct
2 Correct 2 ms 4948 KB correct
3 Correct 2 ms 5012 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 4 ms 5084 KB correct
8 Correct 3 ms 4948 KB correct
9 Correct 2 ms 4948 KB correct
10 Correct 3 ms 4956 KB correct
11 Correct 2 ms 4948 KB correct
12 Correct 3 ms 5012 KB correct
13 Correct 3 ms 4948 KB correct
14 Correct 4 ms 5148 KB correct
15 Correct 3 ms 5076 KB correct
16 Correct 4 ms 5020 KB correct
17 Correct 4 ms 5024 KB correct
18 Correct 3 ms 5076 KB correct
19 Correct 4 ms 5016 KB correct
20 Correct 4 ms 5076 KB correct
21 Correct 4 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 5016 KB correct
26 Correct 4 ms 5012 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 5032 KB correct
31 Correct 4 ms 5076 KB correct
32 Correct 3 ms 5076 KB correct
33 Correct 3 ms 5012 KB correct
34 Correct 54 ms 6896 KB correct
35 Correct 48 ms 6824 KB correct
36 Correct 41 ms 6452 KB correct
37 Correct 9 ms 5076 KB correct
38 Correct 55 ms 6904 KB correct
39 Correct 40 ms 6664 KB correct
40 Correct 35 ms 6548 KB correct
41 Correct 46 ms 6856 KB correct
42 Correct 47 ms 6900 KB correct
43 Correct 16 ms 6228 KB correct
44 Correct 14 ms 5900 KB correct
45 Correct 16 ms 5916 KB correct
46 Correct 13 ms 5844 KB correct
47 Correct 9 ms 5476 KB correct
48 Correct 4 ms 5016 KB correct
49 Correct 6 ms 5276 KB correct
50 Correct 8 ms 5460 KB correct
51 Correct 15 ms 5972 KB correct
52 Correct 16 ms 5912 KB correct
53 Correct 12 ms 5812 KB correct
54 Correct 16 ms 6228 KB correct
55 Correct 17 ms 5972 KB correct
56 Correct 17 ms 5972 KB correct
57 Correct 18 ms 5972 KB correct
58 Correct 3 ms 4948 KB correct
59 Correct 2 ms 4948 KB correct
60 Correct 153 ms 10676 KB correct
61 Runtime error 250 ms 24912 KB Execution killed with signal 6
62 Halted 0 ms 0 KB -