Trouble with multiple indirection

[REDEBOLT]

I am attempting to convert the following C++ program to EBasic:

Code Select Expand

/*
  Name: EXERCISE 3-04
  Book:        Teach Yourself C++
  Copyright: 1990 by Management Information Source, Inc.
  Author: Al Stevens
  Date: 04/07/07 00:22
  Description: The C++ free store: more dynamic array allocation
*/

#include <cstdlib>
#include <iostream>

using namespace std;

int comp(const void *a, const void *b)
{
return strcmp(*(char **)a, *(char **)b);
}

int main(int argc, char *argv[])
{
cout << "How many names at most? ";
int maxnames;
cin >> maxnames;
char **names = new char *[maxnames];
int namect;
for (namect = 0; namect < maxnames; namect++)   {
cout << "Enter a name: ";
char *name = new char[80];
cin >> name;
if (strcmp(name, "end") == 0)
    break;
names[namect] = new char[strlen(name)+1];
strcpy(names[namect], name);
delete name;
}
qsort(names, namect, sizeof(char *), comp);
for (int i = 0; i < namect; i++)
    cout << names[i] << '\n';
for (int i = 0; i < namect; i++)
    delete names[i];
delete names;

cout << "\n\n";
system ("pause"); /* execute M$-DOS' pause command */
return EXIT_SUCCESS;
}

Code Select Expand

' Ex-03-04.eba
' The free store: more dynamic array allocation.
'
$MAIN
AUTODEFINE "off"
$INCLUDE "waitkey$.inc"
DECLARE IMPORT, GetTickCount(),UINT

OPENCONSOLE
DEF time1 AS UINT
DEF time2 AS UINT
time1 = GetTickCount()

int maxnames,namect,i
pointer pname,ppnames
istring name[80]
INPUT "How many names at most? ",maxnames
ppnames=new(pointer,maxnames)
FOR namect=0 TO maxnames-1 STEP 1
INPUT "Enter a name: ",name
IF name="end" THEN BREAKFOR
ppnames[namect]=new(char,LEN(name)+1)
ppnames[namect]=name
' delete pname
NEXT namect

FOR i=0 TO namect-1
PRINT *<string>ppnames[i]
NEXT i

'region
SETPRECISION (3)
time2 = GetTickCount()
PRINT:PRINT (time2-time1), "ms."
PRINT:PRINT "Done..."
PRINT:PRINT "Press any key to end program."
PRINT

WaitKey$()

CLOSECONSOLE
END
'endregion


. . . and I'm getting nowhere.

[LarryMc]

This should get you a little closer but not exactly there.

Code Select Expand

$MAIN
AUTODEFINE "off"

DECLARE IMPORT, GetTickCount(),UINT

OPENCONSOLE
DEF time1 AS UINT
DEF time2 AS UINT
time1 = GetTickCount()

int maxnames,namect,i
pointer pname,ppnames[100]
istring name[80]
INPUT "How many names at most? ",maxnames
ppnames=new(pointer,maxnames)
FOR namect=0 TO maxnames-1 STEP 1
INPUT "Enter a name: ",name
IF name="end" THEN BREAKFOR
ppnames[namect]=new(string,1)
#<string>ppnames[namect]=name
' delete pname
NEXT namect

FOR i=0 TO namect-1
PRINT #<string>ppnames[i]
NEXT i

'region
SETPRECISION (3)
time2 = GetTickCount()
PRINT:PRINT (time2-time1), "ms."
PRINT:PRINT "Done..."
PRINT:PRINT "Press any key to end program."
PRINT

do:until inkey$<>""

CLOSECONSOLE
END

Larry

[REDEBOLT]

Thanks, Larry.

That was most helpful.

[sapero]

The POINTER as type for NEW is still not working, I've used an INT instead. Added also two optimizations:
- "name  = new" moved outside the loop
- "delete names" moved to previous loop with cout.
The comparing function for qsort must be cdecl:

Code Select Expand

$include "stdio.inc"
$include "string.inc"


declare cdecl comp(pointer a, pointer b),int

sub comp(pointer a, pointer b),int
return strcmp(*<pointer>a, *<pointer>b)
endsub


'int main(int argc, char *argv[])
int maxnames
int namect
pointer name
pointer names
int i

input "How many names at most? ", maxnames
names = new(int, maxnames)
name  = new(char, 80) /*moved outside for{}, why allocate/delete multiple times?*/

for namect = 0 to maxnames-1

input "Enter a name: ", *<string>name

if (strcmp(name, "end") = 0) then _
    breakfor

*<pointer>names[namect] = new(char, strlen(name)+1)
strcpy(*<pointer>names[namect], name)

next namect

delete name
qsort(names, namect, len(pointer), &comp)

for i = 0 to namect-1
puts(*<pointer>names[i])
delete *<pointer>names[i] /*moved here from next for{}*/
next i

delete names

puts("\n")
_system ("pause")

[REDEBOLT]

Thank you, Sapero.

Very illuminating, as usual.