#include<bits/stdc++.h> using namespace std; int a[10000865],m,n,x,s=0; int main(){ cin>>m>>n; for(int i=1;i<=m;i++){ cin>>a[i]; } sort(a+1,a+m+1); int l,r,mid; for(int i=1;i<=n;i++){ cin>>x; if(x<=a[1]){ s=s+a[1]-x; }else if(x>=a[m]){ s=s+x-a[m]; }else{ l=1; r=m; while(l<=r){ mid=l+r>>1; if(x<=a[mid]) r=mid-1; else l=mid+1; } s=s+min(a[l]-x,x-a[l-1]); } } cout<<s; return 0; }