WA on#8#9

#include<bits/stdc++.h>
using namespace std;
int F,n=1,maxx=-1e9,minn=1e9,fence[501][501];
void dfs(int m){
	cout<<m<<endl;
	for (int i=1;i<=maxx;i++){
		if(fence[m][i]>0){
			fence[m][i]--;
			fence[i][m]--;
			dfs(i);
		}
	}
}
 
int main()
{
	cin>>F;
	int I,J;
	for (int i=1;i<=F;i++){
		cin>>I>>J;
		fence[I][J]++;
		fence[J][I]++;
		maxx=max(maxx,I);
		maxx=max(maxx,J);
		minn=min(minn,J);
	}
	bool k=0;
	for (int i=1;i<=maxx;i++){
		int ans=0;
		for (int j=1;j<=maxx;j++){
			if(fence[i][j]!=0) ans++;
		}
		if(ans%2==1){
			n=i;
			k=1;
			break;
		}
	}
	if(!k){
		n=minn;
	}
	dfs(n);
	
	return 0;
}