2022/8/20 总结

#include<bits/stdc++.h>
using namespace std;

inline int read(){
	int s=0,f=1;
	char ch=getchar();
	while(!isdigit(ch)){
		if(ch=='-') f=-1;
		ch=getchar();
	}
	while(isdigit(ch)){
		s=s*10+int(ch-'0');
		ch=getchar();
	}
	return s*f;
}

const int N=55;

#define re register

struct memr{
	int x,y;
};

int n;
int a[N][N],b[N][N];
int c[N*N],tot=0;
int cl;
vector<memr>nxt[N*N];

inline int rk(int x){
	return lower_bound(c+1,c+cl+1,x)-c;
}

int main(){
//	freopen("map.in","r",stdin);
//	freopen("map.out","w",stdout);
	n=read();
	for(re int i=1;i<=n;++i)
		for(re int j=1;j<=n;++j){
			a[i][j]=read();
			c[++tot]=a[i][j];
		}
	sort(c+1,c+tot+1);
	cl=unique(c+1,c+tot+1)-c-1;
	for(re int i=1;i<=n;++i)
		for(re int j=1;j<=n;++j){
			b[i][j]=read();
			nxt[rk(b[i][j])].push_back((memr){i,j});
		}
	int ans=0;
	for(re int i=1;i<=n;++i){
		for(re int j=1;j<=n;++j){
			int r=rk(a[i][j]);
			for(re int k=0;k<nxt[r].size();++k){
				int x=nxt[r][k].x;
				int y=nxt[r][k].y;
				int cnt=0;
				bool s=1;
				while(s){
					++cnt;
					if(x+cnt-1>n || y+cnt-1>n) break;
					if(i+cnt-1>n || j+cnt-1>n) break;
					for(re int p=x,q=i;p<x+cnt;++p,++q)
						if(a[q][j+cnt-1]!=b[p][y+cnt-1]){
							s=0;
							break;
						}
					for(re int p=y,q=j;p<y+cnt-1 && s;++p,++q)
						if(a[i+cnt-1][q]!=b[x+cnt-1][p]){
							s=0;
							break;
						}
				}
				ans=max(ans,cnt-1);
			}
			if(ans>n-j+1)
				break;
		}
		if(ans>n-i+1)
			break;
	}
	printf("%d",ans);
	return 0;
}