noip 2018 Day2 T1 旅行

暴力删边，暴力枚举

#include <bits/stdc++.h>

using namespace std;

#define MAXM 5010

inline int read()
{
    int x = ,ff = ;char ch = getchar();
    while(!isdigit(ch))
    {
        if(ch == '-') ff = -;
        ch = getchar();
    }
    while(isdigit(ch))
    {
        x = (x << ) + (x << ) + (ch ^ );
        ch = getchar();
    }
    return x * ff;
}

inline void write(int x)
{
    if(x < ) putchar('-'),x = -x;
    if(x > ) write(x / );
    putchar(x %  + '');
}

int a,b,x,y,dx,dy,top = ,c[MAXM],vis[MAXM],T[MAXM],m[MAXM],e[MAXM][];
vector < int > q[MAXM];

inline void dfs(int x)
{

    T[++top] = x; vis[x] = true;
    int l = q[x].size();
    for(int i = ;i < l;++i)
    {
        int y = q[x][i];
        if((vis[y]) || (x == dx && y == dy) || (x == dy && y == dx)) continue;
        dfs(y);
    }
    return ;
}

inline void check()
{
    for(int i = ;i <= a;++i)
    {
        if(m[i] != T[i])
        {
            if(m[i] < T[i]) return ;
            break;
        }
    }
    for(int i = ;i <= a;++i)
    m[i] = T[i];
}

int main()
{
    memset(m,0x3f,sizeof(m));
    a = read(); b = read();
    for(int i = ;i <= b;++i)
    {
        int x,y;
        x = read(); y = read();
        q[x].push_back(y);
        q[y].push_back(x);
        e[i][] = x;
        e[i][] = y;
    }
    for(int i = ;i <= a;++i)
        sort(q[i].begin(),q[i].end());
    if(b == a - )
    {
        dx = -; dy = -;
        dfs();
        for(int i = ;i <= a;++i)
        write(T[i]),putchar(' ');
    }
    else
    {
        for(int i = ;i <= b;++i)
        {
            top = ;
            dx = e[i][];
            dy = e[i][];
            memset(T,,sizeof(T));
            memset(vis,false,sizeof(vis));
            dfs();
            if(top != a) continue;
            check();
        }
        for(int i = ;i <= a;++i)
        write(m[i]),putchar(' ');
    }
    return ;
}