#include<stdio.h>
#include<stdlib.h>
typedef struct node {
	int data;
	struct node *next;
} Node;
Node *p,*r;
typedef struct head {
	int data;
	struct node *ptr;
} Head;
Head heads[100005];
int visited[100005];
void DFS(Head rot) {
//	if(visited[rot.data]){
//		return ;
//	}//and if it is necassary
	printf("%d ",rot.data);
	visited[rot.data]=1;
	Node *q;
	q=rot.ptr;
	while(q!=NULL) {
		if(!visited[q->data]) {
			DFS(heads[q->data]);
//			visited[q->data]=1;//after ..I will test if this is necessary
		}
		q=q->next;
	}
	return ;
}
void BFS() {
	Head queue[100005],temp;
	Node *q;
	int front=0,rear=0,trear;
	queue[0]=heads[1]; 
	while(front<=rear) {
		trear=rear;
		while(front<=trear) {
			temp=queue[front];
			if(!visited[temp.data]){
				printf("%d ",temp.data);
				visited[temp.data]=1;
				q=heads[temp.data].ptr;
				while(q!=NULL){
					if(!visited[q->data])
					queue[++rear]=heads[q->data];
					q=q->next;
				}
			}
			front++;
		}
	}
}
int main() {
	int n,m,i,a,b;
	scanf("%d%d",&n,&m);
	for(i=0; i<=n; i++) {//initial
		heads[i].ptr=NULL;
		heads[i].data=i;
	}
	for(i=0; i<m; i++) {//build graph
		scanf("%d%d",&a,&b);
//		printf("%d%d\n",a,b);
		p=(Node *)malloc(sizeof(Node));
		p->data=b;
		p->next=NULL;
		if(!heads[a].ptr) {
			heads[a].data=a;
			heads[a].ptr=p;
		} else {
			r=heads[a].ptr;
			if(r->data>b){
				p->next=r;
				heads[a].ptr=p;
				continue;
			}
			while(r->next!=NULL&&r->next->data<b) {//忘记了排序 
				r=r->next;
			}
			p->next=r->next;//没连上啊
			r->next=p;
		}
	}
	DFS(heads[1]);
	printf("\n");
	for(i=0; i<100005; i++) {
		visited[i]=0;
	}
	BFS();
	return 0;
}