#include<bits/stdc++.h>
using namespace std;
int n,a[200][200],m,b[200][200],c;
int main(){
cin>>n>>m;
for(int i=1;i<=n;i++){
	for(int j=1;j<=m;j++){
		cin>>a[i][j];
	}
}
for(int i=1;i<=n;i++){
	for(int j=1;j<=m;j++){
		cin>>b[i][j]; 
	}
}
for(int i=1;i<=n;i++){
	for(int j=1;j<=m;j++){
	if(a[i][j]==b[i][j]) c++;
	
	}
}
printf("%.2f",c*1.0/(n*m)*100);

}

	
/**************************************************************
	Problem: 1407
	User: lihean
	Language: C++
	Result: Accepted
	Time:13 ms
	Memory:2388 kb
****************************************************************/