#include<algorithm>
#include<vector>
#include<math.h>
using namespace std;

int main()
{
    int n, m, temp;
    cin >> n >> m;
    vector<int> vea, veb, vetemp;
    int total_a = 0, total_b = 0;
    for (int i = 0; i<n; i++) {
        cin >> temp;
        vea.push_back(temp);
        total_a += temp;
    }
    for (int i = 0; i<m; i++) {
        cin >> temp;
        veb.push_back(temp);
        total_b += temp;
    }
    int res = 0;
    double avg_a = (double)total_a / n, avg_b = (double)total_b / m;
    if (avg_a>avg_b) {
        vetemp = vea; vea = veb; veb = vetemp;
        temp = n; n = m; m = temp;
        temp = total_a; total_a = total_b; total_b = temp;
    }
    sort(veb.begin(), veb.end());
    while (1) {
        if (m == 1) break;
        avg_a = (double)total_a / n;
        avg_b = (double)total_b / m;
        if (avg_a >= avg_b) break;
        int tip1 = lower_bound(veb.begin(), veb.end(), avg_a) - veb.begin();
        int tip2 = lower_bound(veb.begin(), veb.end(), avg_b) - veb.begin();
        if (tip1<tip2) {
            res++;
            total_a += veb[tip1];
            total_b -= veb[tip1];
            n++;
            m--;
            veb.erase(veb.begin() + tip1);
        }
        else break;
    }
    cout << res << endl;
    system("pause");
    return 0;
}