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#include <bits/stdc++.h>
using namespace std;
bool vis[15];
int n;
vector<int>ans;
void dfs(int now,int last){
    if(now==n+1){
        for(int i=0;i<ans.size();i++){printf("%d ",ans[i]);}printf("\n");
    }
    else{
        for(int i=1;i<=n;i++){
            if(!vis[i]){
                if(last==-1){
                    vis[i]=1;
                    ans.push_back(i);
                    dfs(now+1,i%2);
                    vis[i]=0;
                    ans.pop_back();
                }
                else{
                    if(i%2==last)continue;
                    vis[i]=1;
                    ans.push_back(i);
                    dfs(now+1,i%2);
                    vis[i]=0;
                    ans.pop_back();
                }
            }
        }
    }
}
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