Strange Country II 暴力dfs

这题点的个数（<=50）有限， 所以可以纯暴力DFS去搜索

//#pragma comment(linker, "/STACK:16777216") //for c++ Compiler

#include <stdio.h>

#include <iostream>

#include <fstream>

#include <cstring>

#include <cmath>

#include <stack>

#include <string>

#include <map>

#include <set>

#include <list>

#include <queue>

#include <vector>

#include <algorithm>

#define Max(a,b) (((a) > (b)) ? (a) : (b))

#define Min(a,b) (((a) < (b)) ? (a) : (b))

#define Abs(x) (((x) > 0) ? (x) : (-(x)))

#define MOD 1000000007

#define pi acos(-1.0)



using namespace std;



typedef long long           ll      ;

typedef unsigned long long  ull     ;

typedef unsigned int        uint    ;

typedef unsigned char       uchar   ;



template<class T> inline void checkmin(T &a,T b){if(a>b) a=b;}

template<class T> inline void checkmax(T &a,T b){if(a<b) a=b;}



const double eps = 1e-7      ;

const int N = 210            ;

const int M = 1100011*2      ;

const ll P = 10000000097ll   ;

const int MAXN = 10900000    ;



int n;

int g[110][110], vis[110], ans[110];



void init(){

    memset(g, 0, sizeof(g));

}



bool dfs(int pos, int level){

    ans[level] = pos;

    if(level >= n){

        return true;

    }

    for(int i = 1; i <= n; ++i){

        if(i == pos)    continue;

        if(!vis[i] && g[pos][i]){

            vis[i] = 1;

            if(dfs(i, level + 1)){

                return true;

            }

            vis[i] = 0;

        }

    }

}



int main(){

    std::ios::sync_with_stdio(false);

    int i, j, t, k, u, v, numCase = 0;

    cin >> t;

    while(t--){

        init();

        cin >> n;

        for(i = 1; i <= n * (n - 1) / 2; ++i){

            cin >> u >> v;

            g[u][v] = 1;

        }

        for(i = 1; i <= n; ++i){

            memset(vis, 0, sizeof(vis));

            memset(ans, 0, sizeof(ans));

            vis[i] = 1;

            if(dfs(i, 1))   break;

            vis[i] = 0;

        }

        if(i != n + 1){

            for(i = 1; i < n; ++i){

                cout << ans[i] << ' ';

            }

            cout << ans[n] << endl;

        } else{

            cout << "Impossible" << endl;

        }

    }



    return 0;

}