include <bits/stdc++.h>

using namespace std; int a[105][105]; int main()

{

int n, m, ans = 0;
cin >> n >> m;
for (int i = 1; i <= n * 2; 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++) {
		if (a[i][j] == a[n + i][j]) {

			ans++;
		}
	}

cout << ans;
return 0;

}