#include <bits/stdc++.h>
using namespace std;
int a[110][110],b[110][110],m,n;
double s;
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]) {
				s ++;
			}	
		}
	}
	cout << fixed << setprecision (2) << s / (n * m) * 100 << endl;
	return 0;
}