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#include<stdio.h>
typedef struct{
    int data[100];
    int size;
}List;

void makenull_list(List *pL) {
    pL->size=0;
}

void pushback(List *pL, int x) {
    pL->data[pL->size]=x;
    pL->size++;
}

int element_at(List *pL, int i) {
    return pL->data[i-1];
}

void print_list(List *pL) {
    int i;
    for(i=1; i<=pL->size; i++) {
        printf("%d ", element_at(pL, i));
    }
}

typedef struct {
	int A[20][20];
	int n; //So luong dinh
}Graph;

void init_graph(Graph *pG, int n) {
	int i, j;
	pG->n=n;
	for(i=1; i<=n; i++) {
		for(j=1; j<=n; j++)
			pG->A[i][j]=0;	
	}
}

void add_edge(Graph *pG, int x, int y) {
	pG->A[x][y]=1;
	pG->A[y][x]=1;
}

//Kiem tra lang gieng x, y phai lang gieng khong?
int adjecent(Graph *pG, int x, int y) {
	return pG->A[x][y];
}

void print_graph(Graph *pG) {
	int i, j;
	for(i=1; i<=pG->n; i++) {
		for(j=1; j<=pG->n; j++) 
			printf("%d ", pG->A[i][j]);
		printf("\n");
	}
}

List neighbors(Graph *G, int x) {
	int i;
	List list;
	makenull_list(&list);
	for(i=1; i<=G->n; i++)
		if(adjecent(G, x, i)==1) 
			pushback(&list, i);
	return list;
}

typedef struct {
	int data[100];
	int front, rear;
} Queue;
void make_null_queue(Queue* Q) {
	Q->front = 0;
	Q->rear = -1;
}
void push(Queue* Q, int x) {
	Q->rear++;
	Q->data[Q->rear] = x;
}
int top(Queue* Q) {
	return Q->data[Q->front];
}
void pop(Queue* Q) {
	Q->front++;
}
int empty(Queue* Q) {
	return Q->front > Q->rear;
}

void breath_first_search(Graph* G) {
	Queue frontier;
	int mark[100];
	make_null_queue(&frontier);
/* Kh?i t?o mark, chua d?nh nào du?c xét */
	int j;
	for (j = 1; j <= G->n; j++)
		mark[j] = 0;
/* Ðua 1 vào frontier */
	push(&frontier, 1);
	mark[1] = 1;
/* Vòng l?p chính dùng d? duy?t */
	while (!empty(&frontier)) {
/* L?y ph?n t? d?u tiên trong frontier ra */
		int x = top(&frontier); pop(&frontier);
		printf("%d\n", x);
/* L?y các d?nh k? c?a nó */
		List list = neighbors(G, x);
/* Xét các d?nh k? c?a nó */
		for (j = 1; j <= list.size; j++) {
			int y = element_at(&list, j);
			if (mark[y] == 0) {
				mark[y] = 1;
				push(&frontier, y);
			}
		}
	}
}
int main() {
	//freopen("dt.txt", "r", stdin);
    int i, n, m, u, v;
    Graph G;
    scanf("%d%d", &n, &m);
    init_graph(&G, n);
    for(i=1; i<=m; i++) {
        scanf("%d%d", &u, &v);
        add_edge(&G, u, v);
    }
    //print_graph(&G);
    breath_first_search(&G);
    return 0;
}