#include <iostream>#include <cstdlib>#include <cstring>#include <cstdio>using namespace std;#define maxn 10005#define maxm 100005struct Edge{ int v, next;}edge[maxm];int n, m;int head[maxn];int ecount;bool vis[maxm];void addedge(int a, int b){ edge[ecount].v = b; edge[ecount].next = head[a]; head[a] = ecount++;}void dfs(int a){ for (int i = head[a]; i != -1; i = edge[i].next) { if (vis[i]) continue; int v= edge[i].v; vis[i] = true; dfs(v); } printf("%dn", a + 1);}int main(){ memset(head, -1, sizeof(head)); ecount = 0; scanf("%d%d", &n, &m); for (int i = 0; i < m; i++) { int a, b; scanf("%d%d", &a, &b); a--; b--; addedge(a, b); addedge(b, a); } memset(vis, 0, sizeof(vis)); dfs(0); return 0;}
