include[HTML_REMOVED]
include[HTML_REMOVED]
using namespace std;
int n,m;
int a[100010];
bool cmp(int a,int b)
{
return a>b;
}
int main()
{
cin>>n>>m;
for(int i = 1;i<=n+m+1;i++)
cin>>a[i];
sort(a+1,a+n+m+1+1,cmp);
int num =0;
for(int i =1;i<=n+1;i++)
{
num = num+a[i];
}
for(int i = n+1+1;i<=n+m+1;i++)
{
num = num-a[i];
}
cout<<num;
}