#include <iostream>
#include <vector>
#include <algorithm>
using namespace std;

int main()
{
    ios_base::sync_with_stdio(false);
    int k, n;
    cin >> k >> n;
    vector<int> a(n), b(n);
    for(int &x : a) {
        cin >> x;
    }
    for(int &x : b) {
        cin >> x;
    }
    sort(a.begin(), a.end());
    sort(b.begin(), b.end());
    long long ret = 0;
    for(int i = 0; i < n; i++) {
        int left = k - a[i];
        if(left < 0) continue;
       int cnt =  (int)(upper_bound(b.begin(), b.end(), left - 1) - b.begin());
        if(cnt >= 0 and cnt <= n) {
            ret += cnt;
        }
    }

    long long all = (long long)(n) * (long long)(n);
    cout << all - ret << endl;
    return 0;
}