#include <bits/stdc++.h>
using namespace std;
using vi = vector<int>;
using pi = pair<int, int>;
using ll = long long int;
using llu = unsigned long long int;
template <typename T1, typename T2, typename T3>
T1 modpow(T1 _a, T2 p, T3 mod) {
  assert(p >= 0);
  ll ret = 1, a = _a;
  if (a < 0) {
    a %= mod;
    a += mod;
  }
  if (a >= mod) {
    a %= mod;
  }
  for (; p > 0; p /= 2) {
    if (p & 1) ret = ret * a % mod;
    a = a * a % mod;
  }
  return ret;
}
constexpr int dx[] = {-1, 0, 1, 0, 1, 1, -1, -1};
constexpr int dy[] = {0, -1, 0, 1, 1, -1, 1, -1};
constexpr auto PI = 3.14159265358979323846L;
constexpr auto oo = numeric_limits<llu>::max();
constexpr auto eps = 1e-6;
constexpr auto mod = 1000000007;
constexpr int mx = -1;
vi a, b;
llu solve(vi a, vi b) {
  int na = (int((a).size())), nb = (int((b).size()));
  llu sa = accumulate((a).begin(), (a).end(), 0ll);
  llu sb = accumulate((b).begin(), (b).end(), 0ll);
  llu ans = oo;
  ans = min(sa * (int((b).size())), sb * (int((a).size())));
  for (int i = ((0)), _i = (((int((b).size()))) - 1); i <= _i; ++i) {
    sb -= b[i];
    llu cur = sa * (i + 1) + sb;
    ans = min(ans, cur);
  }
  return ans;
}
int main() {
  int m, n, x;
  cin >> m >> n;
  for (int i = ((0)), _i = ((m)-1); i <= _i; ++i) {
    cin >> x;
    a.push_back(x);
  }
  for (int i = ((0)), _i = ((n)-1); i <= _i; ++i) {
    cin >> x;
    b.push_back(x);
  }
  sort((a).begin(), (a).end());
  reverse((a).begin(), (a).end());
  sort((b).begin(), (b).end());
  reverse((b).begin(), (b).end());
  auto ans = min(solve(a, b), solve(b, a));
  cout << ans << endl;
  return 0;
}
