#include<bits/stdc++.h>
using namespace std;
namespace my_std{
	#define ll long long
	#define bl bool
	ll my_pow(ll a,ll b,ll mod){
		ll res=1;
		if(!b) return 1;
		while(b){
			if(b&1) res=(res*a)%mod;
			a=(a*a)%mod;
			b>>=1;
		}
		return res;
	}
	ll qpow(ll a,ll b){
		ll res=1;
		if(!b) return 1;
		while(b){
			if(b&1) res*=a;
			a*=a;
			b>>=1;
		}
		return res;
	}
	#define db double
	#define pf printf
	#define pc putchar
	#define fr(i,x,y) for(register ll i=(x);i<=(y);i++)
	#define pfr(i,x,y) for(register ll i=(x);i>=(y);i--)
	#define go(u) for(ll i=head[u];i;i=e[i].nxt)
	#define enter pc('\n')
	#define space pc(' ')
	#define fir first
	#define sec second
	#define MP make_pair
	#define il inline
	#define inf 8e18
	#define random(x) rand()*rand()%(x)
	#define inv(a,mod) my_pow((a),(mod-2),(mod))
	il ll read(){
		ll sum=0,f=1;
		char ch=0;
		while(!isdigit(ch)){
			if(ch=='-') f=-1;
			ch=getchar();
		}
		while(isdigit(ch)){
			sum=sum*10+(ch^48);
			ch=getchar();
		}
		return sum*f;
	}
	il void write(ll x){
		if(x<0){
			x=-x;
			pc('-');
		}
		if(x>9) write(x/10);
		pc(x%10+'0');
	}
	il void writeln(ll x){
		write(x);
		enter;
	}
	il void writesp(ll x){
		write(x);
		space;
	}
}
using namespace my_std;
map<pair<ll,ll>,bl> mp;
ll n,m,pre[300030],suf[300030];
void merge(ll x,ll y,ll z){
	pre[y]=x;
	suf[x]=y;
	pre[z]=y;
	suf[y]=z;
}
void solve(){
	ll x=0,typ=1,ed=2;
	if(mp.count(MP(1,2))) x=1;
	else x=2;
	pre[2]=1;
	suf[1]=2;
	fr(i,3,n){
		if((typ==1&&!suf[x])||(typ==2&&!pre[x])){
			ll y=pre[ed],yy=ed,t1=mp.count(MP(i,y)),t2=mp.count(MP(i,yy));
			if(!t1&&!t2){
				merge(y,i,yy);
				typ=1;
				x=yy;
			}
			else if(!t1&&t2){
				merge(y,i,yy);
				typ=1;
				x=i;
			}
			else if(t1&&!t2){
				merge(y,yy,i);
				typ=1;
				x=ed=i;
			}
			else{
				merge(y,i,yy);
				typ=1;
				x=y;
			}
		}
		else if((typ==1&&!pre[x])||(typ==2&&!suf[x])){
			ll y=pre[ed],yy=ed,t1=mp.count(MP(i,y)),t2=mp.count(MP(i,yy));
			if(!t1&&!t2){
				merge(y,i,yy);
				typ=2;
				x=y;
			}
			else if(!t1&&t2){
				merge(y,yy,i);
				typ=2;
				x=ed=i;
			}
			else if(t1&&!t2){
				merge(y,i,yy);
				typ=2;
				x=i;
			}
			else{
				merge(y,i,yy);
				typ=2;
				x=yy;
			}
		}
		else if(typ==1){
			ll y=pre[x],yy=x,yyy=suf[x],t1=mp.count(MP(i,y)),t2=mp.count(MP(i,yy)),t3=mp.count(MP(i,yyy));
			if(!t1&&!t2){
				merge(y,i,yy);
				x=yy;
			}
			else if(!t1&&t2){
				merge(y,i,yy);
				x=i;
			}
			else if(t1&&!t2){
				merge(yy,i,yyy);
				if(!t3) x=yyy;
				else x=i;
			}
			else{
				merge(y,i,yy);
				x=y;
			}
		}
		else{
			ll y=pre[x],yy=x,yyy=suf[x],t1=mp.count(MP(i,y)),t2=mp.count(MP(i,yy)),t3=mp.count(MP(i,yyy));
			if(!t1&&!t2){
				merge(y,i,yy);
				x=y;
			}
			else if(!t1&&t2){
				merge(yy,i,yyy);
				if(t3) x=yyy;
				else x=i;
			}
			else if(t1&&!t2){
				merge(y,i,yy);
				x=i;
			}
			else{
				merge(y,i,yy);
				x=yy;
			}
		}
	}
}
int main(){
	n=read();
	m=read();
	fr(i,1,m){
		ll u=read(),v=read();
		mp[MP(u,v)]=mp[MP(v,u)]=1;
	}
	solve();
	for(ll i=1;i;i=suf[i]) writesp(i);
}