POJ2230-还是简单的欧拉回路求解

#include <cstring>#include <iostream>#include <cstdio>#include <vector>using namespace std;const int NN=10002;vector<int> ans;vector<int> adj[NN];int n,m,cur[NN];void dfs(int u){    for (int &i=++cur[u]; i<adj[u].size(); i++)    {        int v=adj[u][i];        dfs(v);        ans.push_back(v);    }}int main(){    scanf("%d%d",&n,&m);    for (int i=1; i<=n; i++)    {        adj[i].clear();        cur[i]=-1;    }    for (int i=1; i<=m; i++)    {        int u,v;        scanf("%d%d",&u,&v);        adj[u].push_back(v);        adj[v].push_back(u);    }    ans.clear();    dfs(1);    printf("1\n");    for (int i=ans.size()-1; i>=0; i--) printf("%d\n",ans[i]);    return 0;}