Submission #1819907

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Source Code Expand

#include <algorithm>
#include <climits>
#include <cmath>
#include <cstdio>
#include <cstdlib>
#include <ctime>
#include <iostream>
#include <sstream>
#include <functional>
#include <map>
#include <string>
#include <cstring>
#include <vector>
#include <queue>
#include <stack>
#include <deque>
#include <set>
#include <list>
#include <numeric>
using namespace std;
typedef long long ll;
typedef unsigned long long ull;
typedef pair<ll,ll> P;
const double PI = 3.14159265358979323846;
const double EPS = 1e-12;
const ll INF = 1LL<<29;
const ll mod = 1e9+7;
#define rep(i,n) for(int (i)=0;(i)<(ll)(n);++(i))
#define repd(i,n,d) for(ll (i)=0;(i)<(ll)(n);(i)+=(d))
#define all(v) (v).begin(), (v).end()
#define pb(x) push_back(x)
#define mp(x,y) make_pair((x),(y))
#define mset(m,v) memset((m),(v),sizeof(m))
#define chmin(X,Y) ((X)>(Y)?X=(Y),true:false)
#define chmax(X,Y) ((X)<(Y)?X=(Y),true:false)
#define fst first
#define snd second
#define UNIQUE(x) (x).erase(unique(all(x)),(x).end())
template<class T> ostream &operator<<(ostream &os, const vector<T> &v){int n=v.size();rep(i,n)os<<v[i]<<(i==n-1?"":" ");return os;}

#define N 100010
ll n, m;
vector<int> res, g[N];
bool used[N];

void dfs(int u){
	used[u] = true;
	res.push_back(u);
	for(int v: g[u]) if(!used[v]){
		dfs(v);
		return;
	}
}

int main(){
	cin>>n>>m;
	rep(i, m){
		int a, b;
		cin>>a>>b; a--; b--;
		g[a].push_back(b);
		g[b].push_back(a);
	}
	dfs(0);
	reverse(all(res));
	res.pop_back();
	used[0] = false;
	dfs(0);
	cout<<res.size()<<endl;
	rep(i, res.size()) cout<<res[i]+1<<" "; cout<<endl;
	return 0;
}

Submission Info

Judge Result