记录编号	22538	评测结果	AAAAAAAAAA
题目名称	象棋比赛	最终得分	100
用户昵称	sr-end	是否通过	通过
代码语言	Pascal	运行时间	0.102 s
提交时间	2010-11-19 16:02:16	内存使用	0.69 MiB

program aa;
var
f,f1:text;
n,k,i,j,l:longint;
a:array[1..100000] of longint;
br:array[1..100000] of integer;
procedure Sort(l, r: longint);
var
  i, j, x, y: longint;
begin
  i := l; j := r; x := a[(l+r) DIV 2];
  repeat
    while a[i] < x do i := i + 1;
    while x < a[j] do j := j - 1;
    if i <= j then
    begin
      y := a[i]; a[i] := a[j]; a[j] := y;
      i := i + 1; j := j - 1;
    end;
  until i > j;
  if l < j then Sort(l, j);
  if i < r then Sort(i, r);
end;
procedure Sortt(l, r: longint);
var
  i, j, x, y: longint;
begin
  i := l; j := r; x := br[(l+r) DIV 2];
  repeat
    while br[i] < x do i := i + 1;
    while x < br[j] do j := j - 1;
    if i <= j then
    begin
      y := br[i]; br[i] := br[j]; br[j] := y;
      i := i + 1; j := j - 1;
    end;
  until i > j;
  if l < j then Sortt(l, j);
  if i < r then Sortt(i, r);
end;
begin
l:=0;
assign(f,'chess.in');assign(f1,'chess.out');
reset(f);rewrite(f1);
readln(f,n,k);
for i:=1 to n do
readln(f,a[i]);
sort(1,n);
for i:=1 to n-1 do
 br[i]:=a[i+1]-a[i];
 sortt(1,n-1);
for i:=1 to k do
l:=l+br[i];
 write(f1,l);
 close(f);close(f1);
end.