#include <bits/stdc++.h>

using namespace std;

int main() {
    int a[100][100] = {0}, b[100][100] = {0};
    int m, n;
    cin >> m >> n;
    for (int i = 0; i < m; ++i) {
        for (int j = 0; j < n; ++j) {
            cin >> a[i][j];
        }
    }
    for (int i = 0; i < m; ++i) {
        for (int j = 0; j < n; ++j) {
            cin >> b[i][j];
        }
    }

    int samecount = 0;
    for (int i = 0; i < m; ++i) {
        for (int j = 0; j < n; ++j) {
            if (a[i][j] == b[i][j])samecount++;
        }
    }
    //保留两位小数输出
    cout << fixed << setprecision(2) << 100 * (samecount * 1.0) / (m * n) << endl;
    return 0;
}