#include<bits/stdc++.h>
using namespace std;
int n,m;
int money;
struct abc
{
	int dj;
	int fx;
}qkl[10006];
bool cmp(abc &x,abc &y)
{
	return x.dj>y.dj;
}
int main()
{
	scanf("%d%d",&n,&m);
	for(int i=1;i<n;i++)
	{
		int ljj;
		scanf("%d",&ljj);
		qkl[i].fx=0;
		qkl[i].dj=ljj;
	}
	for(int i=1;i<m;i++)
	{
		int ljj;
		scanf("%d",&ljj);
		qkl[i+n-1].fx=1;
		qkl[i+n-1].dj=ljj;
	}
	int z=n+m-2;
	int h=1;
	int s=1;
	sort(qkl+1,qkl+z+1,cmp);
	for(int i=1;i<=z;i++)
	{
		if(qkl[i].fx==0)
		{
			money+=s*qkl[i].dj;
			h++;	
		}
		if(qkl[i].fx==1)
		{
			money+=h*qkl[i].dj;
			s++;
		}
	}
	printf("%d",money);
	return 0;
}