Отсортировать по убыванию положительные элементы массива методом выбора - VB

#include<iostream.h>
#include<conio.h>
#include<stdlib.h>
void sort (int k[],int);
void main()
{ 
  int i,j,n,k,x[20],b[20];
  clrscr();
  gotoxy(29,4);
  cout<<"\Laboratornaya rabota N1";
  gotoxy(12,6);
  cout<<"\Otsortirovat' po ubiyvaniy pologitel'nye elementy massiva";
  gotoxy(29,7);
  cout<<"\metodom vybora";
  gotoxy(45,21);
  cout<<"Vypolnil student Aleksandrov Albert";
  getch();
  clrscr();
  cout<<"\n vvedite n ";
  cin>>n;
  randomize();
  for(i=0;i<n;i++)
  x[i]=random(40)-20;
  cout<<"ishodniy massiv\n";
  for (i=0;i<n;i++)
  cout<<x[i]<<" "; cout<<endl;
  k=-1;
  for (i=0;i<n;i++)
  if (x[i]>0)
{
  k++;b[k]=x[i];
       }
 cout<<"massiv iz pologitel'nyh elementov\n";
  for(i=0;i<=k;i++)cout<<b[i]<<"    ";
  cout<<endl;
  cout<<"posle sortirovki";
  cout<<endl;
  sort(b,k);
  getch();
  }
  void sort(int k[], int n)
{       
    int i,j,im,a;
    for (i=0; i<=n; i++)
    {
        im=i;
        for (j=i+1; j<=n; j++)
            {
            if (k[j]>k[im]) im = j;
            }              
        a=k[i]; k[i]=k[im]; k[im]=a;
        gotoxy(2+i*5,9);
        cout<<("%d ",k[i]);
           
    }
}

Dim m, n As Integer
Dim i, j As Integer
Dim Mas() As Integer
Dim B(10) As Integer
Dim s As Byte
 
Dim a(20) As Integer, str
 
Private Sub Command1_Click()
str = "До сортировки: " & Chr(13)
'добавляем вопрос
If MsgBox("Ввести массив вручную?", vbOKCancel + vbQuestion, "Application") = vbOK Then
    'если нажали "ОК"
    For i = 0 To 20
        a(i) = InputBox("Введите элемент а(" & i & ")")
        str = str & a(i) & " "
    Next i
Else
    'если нажали "Cancel"
    For i = 0 To 20
        a(i) = Int(15 * Rnd - 5)
        str = str & a(i) & " "
    Next i
End If
  
str = str & Chr(13) & "После сортировки: " & Chr(13)
Call Sort
For i = 0 To 20
    str = str & a(i) & " "
Next i
MsgBox str
End Sub
Sub Sort()
Dim j, k
For i = 0 To 20
    k = i
    x = a(i)
    For j = i + 1 To 20
           If a(j) > x Then
                k = j
                x = a(j)
           End If
    Next
    a(k) = a(i)
    a(i) = x
Next i
End Sub
 
Private Sub Command2_Click()
End
End Sub