include

using namespace std;

int main() {

int a[110][110];
int n, m, b = 0;
cin >> n >> m;
for (int c = 1; c <= n * 2; c++) {
	for (int d = 1; d <= m; d++) {
		cin >> a[c][d];
	}
}
for (int c = 1; c <= n; c++) {
	for (int d = 1; d <= m; d++) {
		if (a[c][d] == a[c + n][d]) {
			b++;
		}
	}
}
printf("%d", b);
return 0;

}