program xmz;
var
 f1,f2:text;
 n,k,a,b,sh,min,mm,t,ss:longint;
 x:array[1..100]of longint;
 y:array[1..100]of boolean;
 s:array[1..100]of longint;
 begin
 assign(f1,'chop.in');assign(f2,'chop.out');
 reset(f1);rewrite(f2);
 read(f1,n,k);
 if n<(k+3)*2 then write(f2,'NO') else
 begin
  for a:=1 to n do
   read(f1,x[a]);
  for a:=1 to n-1 do
   if not(y[a]) then
   begin
   min:=99999999;
   for b:=a+1 to n do
    if (not(y[b])) then
     if sqr(x[a]-x[b])<min then begin min:=sqr(x[a]-x[b]);mm:=b;end;
     inc(sh);
     s[sh]:=sqr(x[a]-x[mm]);y[a]:=true;y[mm]:=true;
    end;
  for a:=1 to k+3 do
   for b:=a+1 to sh do
    if s[a]>s[b] then begin t:=x[a];x[a]:=x[b];x[b]:=t;end;
  for a:=1 to k+3 do
   ss:=ss+s[a];
  write(f2,ss);
 end;

 close(f1);close(f2);
end.