using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace _1788
{
    class Program
    {
        static void Main(string[] args)
        {
            string[] input = Console.ReadLine().Split(' ');
            int n = int.Parse(input[0]);
            int m = int.Parse(input[1]);
            int[] g = new int[n];
            int[] b = new int[m];
            input = Console.ReadLine().Split(' ');
            for (int i = 0; i < n; i++)
            {
                g[i] = int.Parse(input[i]);
            }
            input = Console.ReadLine().Split(' ');
            for (int i = 0; i < m; i++)
            {
                b[i] = int.Parse(input[i]);
            }
            int res = int.MaxValue;
            Array.Sort(g);
            Array.Sort(b);
            int ans = 0;
            if (n>=m)
            {
                for (int i = 0; i < n-m; i++)
                {
                    ans += g[i];
                }
                Console.WriteLine(ans);
                return;
            }

            for (int i = 0; i <= n; i++)
            {
                ans = 0;
                for (int j = 0; j < m-i; j++)
                {
                    ans += b[i] * i;
                }
                for (int q = 0; q < n-i; q++)
                {
                    ans += g[q];
                }
                res = Math.Min(res, ans);
            }
            Console.WriteLine(res);
            Console.ReadLine();
        }
    }
}

Edited by author 15.05.2012 20:33