#include<bits/stdc++.h>
using namespace std;
int a[200][200],b[200][200]; 
int main(){
    int n,m,c=0,i,j;
	cin>>n>>m;
	for(i=1;i<=n;i++){
		for(j=1;j<=m;j++){
			cin>>a[i][j];
		}
	} 
	for(i=1;i<=n;i++){
		for(j=1;j<=m;j++){
			cin>>b[i][j];
		}
	} 
	for(i=1;i<=n;i++){
		for(j=1;j<=m;j++){
			if(a[i][j]==b[i][j]){
				c++;
			}
		}
	} 
	printf("%.2f",c*1.0/(n*m)*100);
	return 0;
}

/**************************************************************
	Problem: 1407
	User: xuanhua
	Language: C++
	Result: Accepted
	Time:16 ms
	Memory:2388 kb
****************************************************************/