一个一维数组问题

[haohhz]

A[0..n-1],B[0..m-1],n>m
意思找出数组A中m个小的数组给数组B
例如数组A[1,5,0,9,12,8,3,7),数组B[4]
求B[0,1,3,5]
条件:不能改变数组A的值,不用用其它数组.

[CloneCenter]

作业题？

[haohhz]

是的,帮忙

[GetError]

有意思，研究下

[haohhz]

procedure TForm1.Button1Click(Sender: TObject);
var i,j,m:integer;
A :array[0..9] of integer;
B :array of integer;
OutStr:String;
begin
A[0]:=2;
A[1]:=5;
A[2]:=3;
A[3]:=9;
A[4]:=6;
A[5]:=17;
A[6]:=23;
A[7]:=12;
A[8]:=0;
A[9]:=8;
OutStr:='';
m:=7;
SetLength(B,m);
for j:=0 to m do
begin
if j=0 then
begin
B[j]:=A[0];
for i:=low(A) to high(A) do
begin
if (A[i]<B[j]) then B[j]:=A[i];
end;
end
else
begin
B[j]:=A[0];
for i:=low(A) to high(A) do
begin
if (A[i]>B[j]) then B[j]:=A[i];
end;
for i:=low(A) to high(A) do
begin
if (A[i]<B[j]) and (A[i]>B[j-1]) then B[j]:=A[i];
end;
end;
OutStr:=OutStr+' '+IntToStr(B[j]);
end;
ShowMessage('BÊý×éΪ'+OutStr);
end;

答案是出来了.谁能不能帮我优化一下..

[haohhz]

为什么你这个B不会溢出呢?m+3时候也不会溢出.

  
    for i := 0 to m + 3 do
    OutStr := OutStr + ' ' + IntToStr(B[i]);

条件m<n

[dulei115]

用插入排序

procedure TForm1.Button1Click(Sender: TObject);
var
  i, j, n, m: Integer;
  A: array[0..9] of Integer;
  B: array of Integer;
  OutStr: String;
begin
  A[0] := 2;
  A[1] := 5;
  A[2] := 3;
  A[3] := 9;
  A[4] := 6;
  A[5] := 17;
  A[6] := 23;
  A[7] := 12;
  A[8] := 0;
  A[9] := 8;
  OutStr := '';
  m := 7;
  SetLength(B, m);
  for i := 0 to 9 do
  begin
    n := -1;
    for j := 0 to Min(i - 1, m - 1) do
      if A[i] > B[j] then
        n := j
      else
        Break;
    if n > m - 2 then
      Continue;
    for j := m - 1 downto n + 2 do
      B[j] := B[j - 1];
    B[n + 1] := A[i];
  end;
  for i := 0 to m - 1 do
    OutStr := OutStr + ' ' + IntToStr(B[i]);
  ShowMessage('B：'+ Trim(OutStr));
end;