oj.uz

Submission #778111

# Submission time Handle Problem Language Result Execution time Memory
778111 2023-07-10T06:24:54 Z CSQ31 Simurgh (IOI17_simurgh) C++17
51 / 100
 381 ms 23488 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;
	for(int x:edges){
		if(good[x]==-1)good[x] = 1; //this is a bridge	
	}
	int found = 0;
	vector<int>left;
	for(int i=0;i<m;i++){
		//cout<<good[i]<<" ";
		if(good[i]>=0){
			found+=good[i];
			solved.pb(i);
		}else left.pb(i);
	}
	shuffle(left.begin(),left.end(),seed);
	shuffle(solved.begin(),solved.end(),seed);
	edges.clear();
	/*
	for(int i=0;i<m;i++){
		if(good[i]>=0)continue;
		if(found==n-1)break;
		init(n);
		edge.clear();
		edge.pb(i);
		unite(v[i],u[i]);
		int tot = 0;
		for(int x:solved){
			if(unite(v[x],u[x])){
				edge.pb(x);
				tot+=good[x];
			}
		}
		if(ask() == tot)good[i] = 0;
		else{
			good[i] = 1;
			found++;
		}
		solved.pb(i);
	}*/
	while(sz(left) && found != n-1){
		init(n);
		e.clear();
		for(int x:left){
			if(unite(v[x],u[x]))e.pb(x);
		}
		solve(0,sz(e)-1);
		vector<int>tmp;
		for(int x:left){
			if(good[x] == -1)tmp.pb(x);
			else found+=good[x];
		}
		swap(left,tmp);
	}
	
	
	
	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 2 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 4932 KB correct
9 Correct 2 ms 4948 KB correct
10 Correct 2 ms 4948 KB correct
11 Correct 2 ms 4948 KB correct
12 Correct 2 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 2 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 4932 KB correct
9 Correct 2 ms 4948 KB correct
10 Correct 2 ms 4948 KB correct
11 Correct 2 ms 4948 KB correct
12 Correct 2 ms 4948 KB correct
13 Correct 2 ms 4948 KB correct
14 Correct 4 ms 5076 KB correct
15 Correct 4 ms 5124 KB correct
16 Correct 4 ms 5076 KB correct
17 Correct 4 ms 5076 KB correct
18 Correct 3 ms 5076 KB correct
19 Correct 3 ms 5076 KB correct
20 Correct 4 ms 5128 KB correct
21 Correct 3 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 4948 KB correct
26 Correct 3 ms 5076 KB correct
27 Correct 3 ms 5076 KB correct
28 Correct 2 ms 5076 KB correct
29 Correct 2 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
21.0 / 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 2 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 4932 KB correct
9 Correct 2 ms 4948 KB correct
10 Correct 2 ms 4948 KB correct
11 Correct 2 ms 4948 KB correct
12 Correct 2 ms 4948 KB correct
13 Correct 2 ms 4948 KB correct
14 Correct 4 ms 5076 KB correct
15 Correct 4 ms 5124 KB correct
16 Correct 4 ms 5076 KB correct
17 Correct 4 ms 5076 KB correct
18 Correct 3 ms 5076 KB correct
19 Correct 3 ms 5076 KB correct
20 Correct 4 ms 5128 KB correct
21 Correct 3 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 4948 KB correct
26 Correct 3 ms 5076 KB correct
27 Correct 3 ms 5076 KB correct
28 Correct 2 ms 5076 KB correct
29 Correct 2 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 59 ms 6760 KB correct
35 Correct 56 ms 6724 KB correct
36 Correct 45 ms 6432 KB correct
37 Correct 11 ms 5192 KB correct
38 Correct 56 ms 6752 KB correct
39 Correct 51 ms 6608 KB correct
40 Correct 43 ms 6488 KB correct
41 Correct 60 ms 6848 KB correct
42 Correct 57 ms 6756 KB correct
43 Correct 18 ms 6132 KB correct
44 Correct 15 ms 5828 KB correct
45 Correct 17 ms 5972 KB correct
46 Correct 15 ms 5740 KB correct
47 Correct 9 ms 5460 KB correct
48 Correct 3 ms 5076 KB correct
49 Correct 6 ms 5076 KB correct
50 Correct 8 ms 5460 KB correct
51 Correct 17 ms 5972 KB correct
52 Correct 14 ms 5828 KB correct
53 Correct 13 ms 5796 KB correct
54 Correct 18 ms 6120 KB correct
55 Correct 20 ms 5936 KB correct
56 Correct 20 ms 5972 KB correct
57 Correct 20 ms 5940 KB correct

Subtask #4
0 / 19.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 4948 KB correct
2 Correct 2 ms 4948 KB correct
3 Correct 215 ms 10600 KB correct
4 Runtime error 381 ms 23488 KB Execution killed with signal 6
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 2 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 4932 KB correct
9 Correct 2 ms 4948 KB correct
10 Correct 2 ms 4948 KB correct
11 Correct 2 ms 4948 KB correct
12 Correct 2 ms 4948 KB correct
13 Correct 2 ms 4948 KB correct
14 Correct 4 ms 5076 KB correct
15 Correct 4 ms 5124 KB correct
16 Correct 4 ms 5076 KB correct
17 Correct 4 ms 5076 KB correct
18 Correct 3 ms 5076 KB correct
19 Correct 3 ms 5076 KB correct
20 Correct 4 ms 5128 KB correct
21 Correct 3 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 4948 KB correct
26 Correct 3 ms 5076 KB correct
27 Correct 3 ms 5076 KB correct
28 Correct 2 ms 5076 KB correct
29 Correct 2 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 59 ms 6760 KB correct
35 Correct 56 ms 6724 KB correct
36 Correct 45 ms 6432 KB correct
37 Correct 11 ms 5192 KB correct
38 Correct 56 ms 6752 KB correct
39 Correct 51 ms 6608 KB correct
40 Correct 43 ms 6488 KB correct
41 Correct 60 ms 6848 KB correct
42 Correct 57 ms 6756 KB correct
43 Correct 18 ms 6132 KB correct
44 Correct 15 ms 5828 KB correct
45 Correct 17 ms 5972 KB correct
46 Correct 15 ms 5740 KB correct
47 Correct 9 ms 5460 KB correct
48 Correct 3 ms 5076 KB correct
49 Correct 6 ms 5076 KB correct
50 Correct 8 ms 5460 KB correct
51 Correct 17 ms 5972 KB correct
52 Correct 14 ms 5828 KB correct
53 Correct 13 ms 5796 KB correct
54 Correct 18 ms 6120 KB correct
55 Correct 20 ms 5936 KB correct
56 Correct 20 ms 5972 KB correct
57 Correct 20 ms 5940 KB correct
58 Correct 2 ms 4948 KB correct
59 Correct 2 ms 4948 KB correct
60 Correct 215 ms 10600 KB correct
61 Runtime error 381 ms 23488 KB Execution killed with signal 6
62 Halted 0 ms 0 KB -