#include <bits/stdc++.h>

using namespace std;

int main() {
    //输入+输出重定向
    freopen("../1291.txt", "r", stdin);
    int m, n;
    cin >> m >> n;
    vector<int> a(m + 1, 0);
    vector<int> b(n + 1, 0);
    for (int i = 1; i <= m; i++) {
        cin >> a[i];
    }
    for (int i = 1; i <= n; i++) {
        cin >> b[i];
    }
    int count = 0;
    for (int i = 1; i <= m; i++) {
        for (int j = 1; j <= n; j++) {
            if (a[i] > b[j])count++;
        }
    }
    cout << count << endl;
    //关闭文件
    fclose(stdin);
    return 0;
}