#include using namespace std;

int n,m;

int a[105][105]; int b[105][105];

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];
	
int ans=0;
for (int i=1;i<=n;i++)
for (int j=1;j<=m;j++)
	if (a[i][j] == b[i][j])
		ans++;		
printf("%.2lf",ans*100.0/(n*m));

}