hdu 5128 The E-pang Palace (有技巧的暴力）

this question can be find here

I ‘ve done this question twice and I didn’t make it the last time and I think I should write something about it

this question ask if we can find two rectangle at a map , have no shared edge or point , additionally any of their corners must be located at given point with the maximum area.

there is a trap , you can actually find two rectangle that one of them can contain the other one and it’s legal

and we can find four points that two of them is the diagonal point and check if they satisfy the condition

#include <bits/stdc++.h>
#include <cstring>
using namespace std;
struct node
{
    int x,y;
} p[];
int mp[][];
int check(int a,int b,int c,int d)
{
    int lx1,lx2,ly1,ly2,rx1,rx2,ry1,ry2;
    lx1 = min(p[a].x,p[b].x);
    lx2 = min(p[c].x,p[d].x);

    ly1 = min(p[a].y,p[b].y);
    ly2 = min(p[c].y,p[d].y);

    rx1 = max(p[a].x,p[b].x);
    rx2 = max(p[c].x,p[d].x);

    ry1 = max(p[a].y,p[b].y);
    ry2 = max(p[c].y,p[d].y);

    int res;
    if(lx1==lx2&&ly1==ly2&&rx1==rx2&&ry1==ry2)
        return ;

    if((ry1<ly2)||(ry2<ly1)||(lx1>rx2)||(lx2>rx1))
    {
        res=(rx1-lx1)*(ry1-ly1)+(rx2-lx2)*(ry2-ly2);
        return res;
    }
    if(lx2<lx1&&ly2<ly1&&rx1<rx2&&ry1<ry2)
    {
        res=(rx2-lx2)*(ry2-ly2);
        return res;
    }
    if(lx1<lx2&&ly1<ly2&&rx2<rx1&&ry2<ry1)
    {
        res=(rx1-lx1)*(ry1-ly1);
        return res;
    }
    else
        return ;
}
int main()
{
    ios::sync_with_stdio();
    int n = ;
    while(cin>>n)
    {
        if(n == ) break;
        int ans = ;
        memset(mp,,sizeof(mp));
        for(int i = ; i<n; i++)
        {
            cin>>p[i].x>>p[i].y;
            mp[p[i].x][p[i].y] = ;
        }
        if(n<)
        {
            cout<<"imp"<<endl;
            continue;
        }
        for(int i = ; i<n-; i++)
        {
            for(int j = i+; j<n; j++)
            {
                if( (p[i].x == p[j].x) || (p[i].y == p[j].y) )
                {
                    continue;
                }
                else
                {
                    int a = p[i].x;
                    int b = p[i].y;
                    int c = p[j].x;
                    int d = p[j].y;
                    if(mp[c][b]&& mp[a][d])
                    {
                        for(int k = ; k<n-; k++)
                        {
                            if(k != i && k != j)
                            {
                                for(int l = k+; l<n; l++)
                                {
                                    if( l != i && l != j)
                                    {
                                        if(p[k].x == p[l].x || p[k].y == p[l].y)
                                        {
                                            continue;
                                        }
                                        else
                                        {
                                            if(mp[p[l].x][p[k].y] && mp[p[k].x][p[l].y])
                                            {
                                                ans = max(ans,check(i,j,k,l));
                                            }
                                        }
                                    }
                                }
                            }
                        }
                    }
                    else
                    {
                        continue;
                    }
                }
            }
        }
        if(ans == )
        {
            cout<<"imp"<<endl;
        }
        else
        {
            cout<<ans<<endl;
        }
    }
}