codevs1058

类似于最长不下降子序列

type
  node=record
  up,data,down:longint;
end;
var
  i,j,t,n,max:longint;
  a:array[1..105]of node;
begin
  readln(n);
  for i:=1 to n do
  read(a[i].data);
  for i:=1 to n do
  begin
    for j:=1 to i-1 do
    if a[j].data<a[i].data then
    begin
      if a[j].up>=a[i].up then
      a[i].up:=a[j].up+1;
    end
  end;

  for i:=n downto 1 do
  begin
    for j:=n downto i+1 do
    if a[i].data>a[j].data then
    begin
      if a[j].down>=a[i].down then
      a[i].down:=a[j].down+1;
    end;
  end;
  for i:=1 to n do
  if (a[i].up+a[i].down)>max then max:=a[i].up+a[i].down;
  writeln(n-max-1);
end.

就是扫描两次。。