Submission #396971

#	Time	Username	Problem	Language	Result	Execution time	Memory
396971		The_Blitz	Potemkin cycle (CEOI15_indcyc)	C++17	100 / 100	291 ms	91020 KiB

indcyc

// Restart
// += O(logn) ; + = O(n)
 
//#pragma GCC optimize("Ofast")
//#pragma GCC optimize("unroll-loops")
//#pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,tune=native")
#include<bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp> // Common file
#include <ext/pb_ds/tree_policy.hpp> // Including tree_order_statistics_node_update
 
#define fastio ios_base::sync_with_stdio(0);cin.tie(0)
#define fst first
#define snd second
#define all(x) (x).begin(), (x).end()
#define pb push_back
#define sz size()
#define FORN(i,j,n) for(int i=j; i<(int)n;i++) 
#define FOR(i,n) FORN(i,0,n)
#define FORIT(i,x) for( auto i = x.begin() ; i != x.end() ; i++ )
#define MOD 998244353LL
#define MOD1 1000000007LL
#define LIM 262150
#define ones(x) __builtin_popcount(x)
#define trace(x)    cerr << #x << ": " << x << endl;
#define trace2(x, y) cerr << #x << ": " << x << " | " << #y << ": " << y << endl;
#define trace3(x, y,z) cerr << #x << ": " << x << " | " << #y << ": " << y << " | " << #z << ": " << z << endl;
#define INF 1000000000
#define in(x)  cin>>x;
#define out(x) cout<<x;
#define MAXIMO 1LL<<60

#define loga2(x) __builtin_ctzll(x)
//SOLO PARA POTENCIAS DE 2
 
using namespace std;
using namespace __gnu_pbds;
 
typedef long long ll ;
typedef unsigned long long ull ;
typedef vector <int> vi;
typedef pair <int,int> ii;
typedef pair <int,ii> iii;
typedef vector <string> vs;
typedef vector <ii> vii;
typedef vector <iii> viii;
typedef tree<int,null_type,less<int>,rb_tree_tag,tree_order_statistics_node_update> ordered_set;

int n,r;
bool M[1001][1001] = {0};
vii E;
vii G[1001];

bool vis[200002] ={0};
bool flag[200002] ={0};

vi G2[200002];

stack<int> ans;

void dfs(int start){
	if(flag[start]){
		//trace3(ans.top(), E[ans.top()].fst , E[ans.top()].snd)
		cout<<E[ans.top()].fst; ans.pop();
		while(ans.top() != start){
			//trace3(ans.top(), E[ans.top()].fst , E[ans.top()].snd)
			cout<<" "<<E[ans.top()].fst; ans.pop();
		}
		//trace3(ans.top(), E[ans.top()].fst , E[ans.top()].snd)
		cout<<" "<<E[ans.top()].fst<<"\n";
		exit(0);
	}

	if(vis[start]) return;
	
	vis[start] = true;
	flag[start] = true;
	ans.push(start);
	for (auto v : G2[start]) {
        dfs(v);
    }
    ans.pop();
    flag[start] = false;
}


void go(){
	cin>>n>>r;
	
	E.pb({-1,-1}); // JUST FOR INDEX

	for(int i=1;i<=r;i++){
		int x, y ; cin>>x>>y;
		M[x][y] = M[y][x] = true;
		E.pb({x,y});
		E.pb({y,x});
		G[x].pb({y,2*i-1});
		G[y].pb({x,2*i});
	}

	for(int i=1; i< (int)E.size() ; i++){
		int &v = E[i].fst ; int &u = E[i].snd; 

		for(auto it2: G[u]){
			if(it2.fst != v && !M[it2.fst][v]){
				//trace2(i, it2.snd)
				G2[i].pb(it2.snd);
			}
		}
	}

	for(int i=1; i<(int)E.size() ; i++){
		dfs(i);
	}
	cout<<"no\n";
}


void timer(){
	clock_t begin = clock();
	go();
	clock_t end = clock();
	double time_spent = (double)(end - begin) / CLOCKS_PER_SEC;
	cout<<time_spent<<"\n";
}	

 
int main() {
  //fastio;
  go();
  //timer();
  return 0;
}

• Subtask 1: 10 / 10
• Subtask 2: 10 / 10
• Subtask 3: 10 / 10
• Subtask 4: 10 / 10
• Subtask 5: 10 / 10
• Subtask 6: 10 / 10
• Subtask 7: 10 / 10
• Subtask 8: 10 / 10
• Subtask 9: 10 / 10
• Subtask 10: 10 / 10