CodeForces 596A Wilbur and Swimming Pool

水题。

#include<cstdio>
#include<cstring>
#include<cmath>
#include<algorithm>
using namespace std;

struct X
{
    int x,y;
}s[],tmp[];

int n;

int main()
{
    scanf("%d",&n);
    for(int i=;i<=n;i++)
        scanf("%d%d",&s[i].x,&s[i].y);

    int flag=-;
    for(int i=;i<=n;i++)
    {
        for(int j=;j<=n;j++)
        {
            if(s[i].x!=s[j].x&&s[i].y!=s[j].y)
            {
                flag=;
                tmp[]=s[i];
                tmp[]=s[j];
                tmp[].x=s[i].x; tmp[].y=s[j].y;
                tmp[].x=s[j].x; tmp[].y=s[i].y;
                break;
            }
        }
        if(flag==) break;
    }
    if(flag==-) printf("-1\n");
    else
    {
        flag=;
        for(int i=;i<=n;i++)
        {
            bool f=;
            for(int j=;j<=;j++)
            {
                if(s[i].x==tmp[j].x&&s[i].y==tmp[j].y) f=;
            }
            if(f==) flag=-;
        }
        if(flag==-) printf("-1\n");
        else{
            printf("%d\n",abs(tmp[].x-tmp[].x)*abs(tmp[].y-tmp[].y));
        }
    }

    return ;
}