题目大意:Filya在边长为n的正方形里面, 画了两个矩形。这两个矩形的边与正方形的边平行,且两个长方形没有不能相交(边可以重合)。但是Filya忘记他把两个矩形画在正方形的哪边了,所以他问Sonya在以(x1, y1)为左下顶点和以(x2, y2)为右上顶点的矩形里面,完整包含了几个他之前画的矩形, 问的次数不能超过200次。让你来模拟这个过程。你的输入首先是n(正方形的边长),然后由计算机来问你,你的输入就是回答的答案。
方法二分即可,但是搞不懂为什么用cin, cout就不用清空缓冲区,这个题目清空缓冲区的意义何在?
#include<bits/stdc++.h>
using namespace std;
struct abc
{int x1,y1,x2,y2;void print(){cout<<x1<<" "<<y1<<" "<<x2<<" "<<y2<<" ";}
};
int query(int x1,int y1,int x2,int y2)
{if(x1>x2)swap(x1,x2);if(y1>y2)swap(y1,y2);cout<<"? "<<x1<<" "<<y1<<" "<<x2<<" "<<y2<<endl;int ans;cin>>ans;return ans;
}
abc fi(int xx1,int yy1,int xx2,int yy2)
{abc Ans;int l=yy1,r=yy2,ans=yy1;while(l<=r){int mid=(l+r)/2;if(query(xx1,yy1,xx2,mid)<1)l=mid+1;elser=mid-1,ans=mid;}Ans.y2=ans;l=yy1,r=yy2,ans=yy1;while(l<=r){int mid=(l+r)/2;if(query(xx1,mid,xx2,yy2)<1)r=mid-1;elsel=mid+1,ans=mid;}Ans.y1=ans;l=xx1,r=xx2,ans=xx1;while(l<=r){int mid=(l+r)/2;if(query(xx1,yy1,mid,yy2)<1)l=mid+1;elser=mid-1,ans=mid;}Ans.x2=ans;l=xx1,r=xx2,ans=xx1;while(l<=r){int mid=(l+r)/2;if(query(mid,yy1,xx2,yy2)<1)r=mid-1;elsel=mid+1,ans=mid;}Ans.x1=ans;return Ans;
}
int main()
{int n;scanf("%d",&n);int l=1,r=n,ans=1;while(l<=r){int mid=(l+r)/2;if(query(1,1,mid,n)<1)l=mid+1;elser=mid-1,ans=mid;}if(query(1,1,ans,n)==1&&query(ans+1,1,n,n)==1){abc r1=fi(1,1,ans,n);abc r2=fi(ans+1,1,n,n);cout<<"! ";r1.print();r2.print();return 0;}l=1,r=n,ans=1;while(l<=r){int mid=(l+r)/2;if(query(1,1,n,mid)<1)l=mid+1;elser=mid-1,ans=mid;}abc r1 = fi(1,1,n,ans);abc r2 = fi(1,ans+1,n,n);cout<<"! ";r1.print();r2.print();
}