#include<bits/stdc++.h>
using namespace std;
int main(){
	int main(){
    int a[110][110],b[110][110];
    int n,m,i,j,c = 0;
    cin>>n>>m;
    for(i = 0;i < n;i++){
        for(j = 0;j < m;j++){
            cin>>a[i][j];
        }
    }
     
    for(i = 0;i < n;i++){
        for(j = 0;j < m;j++){
            cin>>b[i][j];
        }
    }
    for(i = 0;i < n;i++){
        for(j = 0;j < m;j++){
            if(a[i][j] == b[i][j]){
                c++;
            }
        }
    }
     
    double r = c * 1.0 / (n * m) * 100;
    cout<<fixed<<setprecision(2)<<r<<endl;
	
	
	
	
    return 0;
}
 


/**************************************************************
	Problem: 1407
	User: zhuanghaoxiang
	Language: C++
	Result: Compile Error
****************************************************************/