#include<bits/stdc++.h>
using namespace std;
int main(){
    int a[105][105],b[105][105],n,m,i,j;
    float h=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]){
    	   h++;
     	}
    }
	
}
    h=h*100/(n*m); 
    printf("%.2f",h);
}
/**************************************************************
	Problem: 1407
	User: lijinkai
	Language: C++
	Result: Accepted
	Time:12 ms
	Memory:2076 kb
****************************************************************/