how to display 12345 as 12,345 ??

[news.hku.hk]

suppose i have:

int price1 = 35000;
int price2 = 600;
int price3 = 8765;
int price4 = 120000;
int price5 = 3800000;

and i want to output to screen the following:

35,000
600
8,765
120,000
3,800,000

what should i do ?? any good function to do this ??

[Marcin Kalicinski]

Re: how to display 12345 as 12,345 ??

U¿ytkownik "news.hku.h k" <billychu@hkusu a.hku.hk> napisa³ w wiadomo¶ci
news:408d1077@n ewsgate.hku.hk. ..[color=blue]
> suppose i have:
>
> int price1 = 35000;
> int price2 = 600;
> int price3 = 8765;
> int price4 = 120000;
> int price5 = 3800000;
>
> and i want to output to screen the following:
>
> 35,000
> 600
> 8,765
> 120,000
> 3,800,000
>
> what should i do ?? any good function to do this ??[/color]

Not in the standard. You'll have to do it yourself. I believe it is quite
simple.

regards,
Marcin

[John Ericson]

Re: how to display 12345 as 12,345 ??

"news.hku.h k" <billychu@hkusu a.hku.hk> wrote in message
news:408d1077@n ewsgate.hku.hk. ..[color=blue]
> suppose i have:
>
> int price1 = 35000;
> int price2 = 600;
> int price3 = 8765;
> int price4 = 120000;
> int price5 = 3800000;
>
> and i want to output to screen the following:
>
> 35,000
> 600
> 8,765
> 120,000
> 3,800,000
>
> what should i do ?? any good function to do this ??
>
>[/color]

You could look up facets, and check out Dinkumware.

[JKop]

Re: how to display 12345 as 12,345 ??



I've done this before. I've adapted it for the purpose of this post, but
here goes (Check for bugs before you use it!):


char szBuffer[30]; //Global Variable

char* GenerateString( unsigned long);

int main(void)
{
cout << GenerateString( 12345);
}


char* GenerateString( unsigned long Numbr)
{
szBuffer[29] = '\0';

char* pChar = &m_szBuffer[28];

unsigned long char_counter = 0;
unsigned long comma_counter = 0;
unsigned long nResult; //will be initialized
unsigned long nTempValue = Numbr;

for(;;)
{
nResult = 0;

//I used to use the method below, but it's FAR too slow
/*
while ( nTempValue >= 10 )
{
nTempValue -= 10;
nResult += 1;
}*/

nResult = nTempValue / 10;
nTempValue %= 10;

*pChar = ( ( '0' ) + ( nTempValue ) );
pChar -= 1;


char_counter +=1;

nTempValue = nResult; //Very Important!

if (!nTempValue) break; //This line prevents ",345" being
generated

char_counter += 1;


if ( comma_counter == 3 )
{
*pChar = ',';
pChar -= 1;
char_counter += 1;
comma_counter = 0;
}
} //End of "For"

return pChar;

}


Hope that helps. Also, you may try incorporating it into a class ( I did! )
and also overide the ostream "<<" operator! That'd be dead handy. I'd post
the class I wrote for it but it had a very specific purpose other than just
genrating these strings.


-JKop

[pembed2003]

Re: how to display 12345 as 12,345 ??

"news.hku.h k" <billychu@hkusu a.hku.hk> wrote in message news:<408d1077@ newsgate.hku.hk >...[color=blue]
> suppose i have:
>
> int price1 = 35000;
> int price2 = 600;
> int price3 = 8765;
> int price4 = 120000;
> int price5 = 3800000;
>
> and i want to output to screen the following:
>
> 35,000
> 600
> 8,765
> 120,000
> 3,800,000
>
> what should i do ?? any good function to do this ??[/color]

Hi,
I am new to C++ too so my solution might not be very good. Anyway, I
will try something like:

void _display_number (int v, int n){
if(v >= 1000){
int r = v % 1000;
_display_number (v / 1000,n);
printf(",%03d", r); // how to translate that into
std::cout<<...?
}else{
printf("%s%d\n" ,n ? "-":"",v);
}
}

void display_number( int v){
_display_number (v < 0 ? -v : v,v < 0);
}

int main(int argc,char** argv){
display_number( 35000);
display_number( 600);
display_number( 8765);
display_number( 120000);
display_number( 3800000);
display_number(-3800000);
}

The program prints something like:

35,000
600
8,765
120,000
3,800,000
-3,800,000

HTH. I am here to learn as well so if anyone can help me improve the
program, I am happy to see it. Thanks!

[John Ericson]

Re: how to display 12345 as 12,345 ??


"JKop" <NULL@NULL.NULL > wrote in message
news:CUcjc.5713 $qP2.13751@news .indigo.ie...[color=blue]
>
>
> I've done this before. I've adapted it for the purpose of[/color]
this post, but[color=blue]
> here goes (Check for bugs before you use it!):
>
>
> char szBuffer[30]; //Global Variable
>
> char* GenerateString( unsigned long);
>
> int main(void)
> {
> cout << GenerateString( 12345);
> }
>
>
> char* GenerateString( unsigned long Numbr)
> {
> szBuffer[29] = '\0';
>
> char* pChar = &m_szBuffer[28];
>
> unsigned long char_counter = 0;
> unsigned long comma_counter = 0;
> unsigned long nResult; //will be initialized
> unsigned long nTempValue = Numbr;
>
> for(;;)
> {
> nResult = 0;
>
> //I used to use the method below, but it's FAR too[/color]
slow[color=blue]
> /*
> while ( nTempValue >= 10 )
> {
> nTempValue -= 10;
> nResult += 1;
> }*/
>
> nResult = nTempValue / 10;
> nTempValue %= 10;
>
> *pChar = ( ( '0' ) + ( nTempValue ) );
> pChar -= 1;
>
>
> char_counter +=1;
>
> nTempValue = nResult; //Very Important!
>
> if (!nTempValue) break; //This line prevents ",345"[/color]
being[color=blue]
> generated
>
> char_counter += 1;
>
>
> if ( comma_counter == 3 )
> {
> *pChar = ',';
> pChar -= 1;
> char_counter += 1;
> comma_counter = 0;
> }
> } //End of "For"
>
> return pChar;
>
> }
>
>
> Hope that helps. Also, you may try incorporating it into a[/color]
class ( I did! )[color=blue]
> and also overide the ostream "<<" operator! That'd be dead[/color]
handy. I'd post[color=blue]
> the class I wrote for it but it had a very specific[/color]
purpose other than just[color=blue]
> genrating these strings.
>
>
> -JKop[/color]

How about (untested code, and YMMV)

#include <iostream>
#include <locale>

int main()
{
using namespace std;
cout.imbue(loca le("English")) ;
cout << 12345 << '\n';
}

;) JE

[news.hku.hk]

Re: how to display 12345 as 12,345 ??

thanks for all of your's help
but i still can't grasp the idea of the algorithm
maybe could anyone explain in words(preferabl y with c++ codes) that how the
algorithm works ??
Thanks

"pembed2003 " <pembed2003@yah oo.com> wrote in message
news:db593abd.0 404261130.2a02b 059@posting.goo gle.com...[color=blue]
> "news.hku.h k" <billychu@hkusu a.hku.hk> wrote in message[/color]
news:<408d1077@ newsgate.hku.hk >...[color=blue][color=green]
> > suppose i have:
> >
> > int price1 = 35000;
> > int price2 = 600;
> > int price3 = 8765;
> > int price4 = 120000;
> > int price5 = 3800000;
> >
> > and i want to output to screen the following:
> >
> > 35,000
> > 600
> > 8,765
> > 120,000
> > 3,800,000
> >
> > what should i do ?? any good function to do this ??[/color]
>
> Hi,
> I am new to C++ too so my solution might not be very good. Anyway, I
> will try something like:
>
> void _display_number (int v, int n){
> if(v >= 1000){
> int r = v % 1000;
> _display_number (v / 1000,n);
> printf(",%03d", r); // how to translate that into
> std::cout<<...?
> }else{
> printf("%s%d\n" ,n ? "-":"",v);
> }
> }
>
> void display_number( int v){
> _display_number (v < 0 ? -v : v,v < 0);
> }
>
> int main(int argc,char** argv){
> display_number( 35000);
> display_number( 600);
> display_number( 8765);
> display_number( 120000);
> display_number( 3800000);
> display_number(-3800000);
> }
>
> The program prints something like:
>
> 35,000
> 600
> 8,765
> 120,000
> 3,800,000
> -3,800,000
>
> HTH. I am here to learn as well so if anyone can help me improve the
> program, I am happy to see it. Thanks![/color]

[rossum]

Re: how to display 12345 as 12,345 ??

On Mon, 26 Apr 2004 21:37:07 +0800, "news.hku.h k"
<billychu@hkusu a.hku.hk> wrote:
[color=blue]
>suppose i have:
>
>int price1 = 35000;
>int price2 = 600;
>int price3 = 8765;
>int price4 = 120000;
>int price5 = 3800000;
>
>and i want to output to screen the following:
>
>35,000
>600
>8,765
>120,000
>3,800,000
>
>what should i do ?? any good function to do this ??
>[/color]
Yet another alternative. This one converts the number into a string
and puts the commas into the string. Not necessarily better, just
different.

rossum


#include <string>
#include <sstream>
#include <iostream>
#include <cstdlib>

std::string comma(int num) {
// Deal with negatives
if(num < 0) { return "-" + comma(std::abs( num)); }

// Convert number to string
std::stringstre am ss;
ss << num;
std::string num_string = ss.str();

// Insert a comma every third position
for (int i = num_string.leng th() - 3; i > 0; i -= 3) {
num_string.inse rt(i, 1, ',');
} // end for

return num_string;
} // end comma()

//---------------------------

int main() {
std::cout << comma(-3800000) << '\n'
<< comma(-120000) << '\n'
<< comma(-35000) << '\n'
<< comma(-8765) << '\n'
<< comma(-600) << '\n'
<< comma(-50) << '\n'
<< comma(-4) << '\n'
<< comma(0) << '\n'
<< comma(4) << '\n'
<< comma(50) << '\n'
<< comma(600) << '\n'
<< comma(8765) << '\n'
<< comma(35000) << '\n'
<< comma(120000) << '\n'
<< comma(3800000) << std::endl;
return EXIT_SUCCESS;
} // end main()





--

The Ultimate Truth is that there is no Ultimate Truth

[Siemel Naran]

Re: how to display 12345 as 12,345 ??

"John Ericson" <jericwahabison @pacbell.net> wrote in message news:Eijjc.1921

This is a good solution. Not sure why everyone is re-inventing the wheel.
[color=blue]
> using namespace std;
> cout.imbue(loca le("English")) ;
> cout << 12345 << '\n';[/color]

But, is there a locale named "English"?

[news.hku.hk]

Re: how to display 12345 as 12,345 ??

Thanks, i see your point
but how to return to the original state??
because i just want to insert the comma in someline while later i just want
to display ordinary numbers.

also, from your quotation, if i add one more cout line after cout << 12345
<<'\n';

i.e. cout << 543532 << '\n';
there will be runtime error.......wha t's up ??

"Siemel Naran" <SiemelNaran@RE MOVE.att.net> wrote in message
news:vNIjc.5671 8$um3.1096370@b gtnsc04-news.ops.worldn et.att.net...[color=blue]
> "John Ericson" <jericwahabison @pacbell.net> wrote in message[/color]
news:Eijjc.1921[color=blue]
>
> This is a good solution. Not sure why everyone is re-inventing the wheel.
>[color=green]
> > using namespace std;
> > cout.imbue(loca le("English")) ;
> > cout << 12345 << '\n';[/color]
>
> But, is there a locale named "English"?
>
>[/color]

[Siemel Naran]

Re: how to display 12345 as 12,345 ??

"news.hku.h k" <billychu@hkusu a.hku.hk> wrote in message news:408f9591
[color=blue]
> Thanks, i see your point
> but how to return to the original state??
> because i just want to insert the comma in someline while later i just[/color]
want[color=blue]
> to display ordinary numbers.[/color]

Haven't tried it yet, but approaches I suggest is: (1) use 2 locales, and
imbue cout with first locale when you want num_put to put comma symbols and
default locale when you don't want comma symbols, (2) create a new type
Amount for which operator<<(ostr eam&, Amount) uses num_put for Amount
objects and this num_put uses comma symbols. See my response in the thread
with subject "convert hex to oct" for this imbue, use_facet, etc. But there
was a C++ magazine that had and maybe still has lots of articles on these
ideas, and I think the articles were by Plauger, so maybe you can browse for
that too.
[color=blue]
> also, from your quotation, if i add one more cout line after cout << 12345
> <<'\n';
>
> i.e. cout << 543532 << '\n';
> there will be runtime error.......wha t's up ??[/color]

No error. I don't know what quotation you're talking about.

[color=blue]
> "Siemel Naran" <SiemelNaran@RE MOVE.att.net> wrote in message
> news:vNIjc.5671 8$um3.1096370@b gtnsc04-news.ops.worldn et.att.net...[color=green]
> > "John Ericson" <jericwahabison @pacbell.net> wrote in message[/color]
> news:Eijjc.1921[color=green]
> >
> > This is a good solution. Not sure why everyone is re-inventing the[/color][/color]
wheel.[color=blue][color=green]
> >[color=darkred]
> > > using namespace std;
> > > cout.imbue(loca le("English")) ;
> > > cout << 12345 << '\n';[/color]
> >
> > But, is there a locale named "English"?
> >
> >[/color]
>
>[/color]

[Joe Hotchkiss]

Re: how to display 12345 as 12,345 ??

news.hku.hk wrote:[color=blue]
> Thanks, i see your point
> but how to return to the original state??
> because i just want to insert the comma in someline while later i
> just want to display ordinary numbers.[/color]

cout.imbue(loca le("C"));

<snip>[color=blue][color=green][color=darkred]
>>> cout.imbue(loca le("English")) ;[/color][/color][/color]
<snip>[color=blue][color=green]
>> But, is there a locale named "English"?[/color][/color]

Since the sample works fine for me, I would assume there is. At least for my
compiler.
Why not try it and see with your compiler?

--
Regards,

Joe Hotchkiss,

http://joe.hotchkiss.com

XXXXXXXXXXXXXXX XXXXXXXXXX
X joe.hotchkiss X
X at baesystems.com X
XXXXXXXXXXXXXXX XXXXXXXXXX

[Jerry Coffin]

Re: how to display 12345 as 12,345 ??

"news.hku.h k" <billychu@hkusu a.hku.hk> wrote in message news:<408d1077@ newsgate.hku.hk >...[color=blue]
> suppose i have:
>
> int price1 = 35000;
> int price2 = 600;
> int price3 = 8765;
> int price4 = 120000;
> int price5 = 3800000;
>
> and i want to output to screen the following:
>
> 35,000
> 600
> 8,765
> 120,000
> 3,800,000
>
> what should i do ?? any good function to do this ??[/color]

You might want to look at commafmt.c at www.snippets.org.

--
Later,
Jerry.

The universe is a figment of its own imagination.

[E. Robert Tisdale]

Re: how to display 12345 as 12,345 ??

news.hku.hk wrote:
[color=blue]
> Suppose that I have:
>
> int price1 = 35000;
> int price2 = 600;
> int price3 = 8765;
> int price4 = 120000;
> int price5 = 3800000;
>
> and that I want to output to screen the following:
>
> 35,000
> 600
> 8,765
> 120,000
> 3,800,000
>
> What should I do? Are there any good functions to do this?[/color]

[color=blue]
> cat main.cc[/color]
#include <iostream>
#include <iomanip>

class Price {
private:
// representation
int I;
public:
// functions
friend
std::ostream& operator<<(std: :ostream& os, const Price& i);
// operators
// implicit
operator int(void) const { return I;}
operator int(void) { return I;}
// constructors
Price(int i = 0): I(i) { }
};

inline
std::ostream& operator<<(std: :ostream& os, const Price& i) {
int q = (int)i/1000;
int r = (int)i%1000;
if (0 < q)
os << Price(q) << ','
<< std::setfill('0 ') << std::setw(3) << r;
else
os << r;
return os;
}

int main(int argc, char* argv[]) {
const
int price[] = {35000, 600, 8765, 120000, 3800000};
const
size_t n = sizeof(price)/sizeof(price[0]);
for (size_t j = 0; j < n; ++j)
std::cout << Price(price[j]) << std::endl;
return 0;
}
[color=blue]
> g++ -Wall -ansi -pedantic -o main main.cc
> ./main[/color]
35,000
600
8,765
120,000
3,800,000

[rossum]

Re: how to display 12345 as 12,345 ??

On 26 Apr 2004 12:30:35 -0700, pembed2003@yaho o.com (pembed2003)
wrote:

[snip OP][color=blue]
>
>Hi,
>I am new to C++ too so my solution might not be very good. Anyway, I
>will try something like:
>[/color]
Show what headers you are including. Code should be compilable as is,
just cut and paste.
[color=blue]
>void _display_number (int v, int n){[/color]
Avoid leading underscores, they are used internally by compilers so if
you pick the wrong name you will get a compilation error. Since
compilers differ this might also make your code non-portable.
Trailing underscores are safer and hence better. So change
_display_number () to display_number_ ().

You have a good self explanatory name for the function, but you use
short cryptic names for the two parameters. Better to change v to
value and n to is_negative so they are more self explanatory.

The second parameter is a yes/no flag so it is better to declare is as
a bool which gives a better indication of its purpose. It is possible
to eliminate this parameter by taking a slightly different approach to
the recursion.
[color=blue]
> if(v >= 1000){[/color]
Put a space between the if and the open bracket: if (value >= 1000) {.
This is to differentiate it from function calls. ^--added space
[color=blue]
> int r = v % 1000;[/color]
Another short cryptic variable name. Change it to something
meaningful.
[color=blue]
> _display_number (v / 1000,n);[/color]
Better to put a space after the comma which separates the parameters.
[color=blue]
> printf(",%03d", r); // how to translate that into
>std::cout<<... ?[/color]
Better to put a space after the second comma which separates the
parameters.

For cout look up the I/O manipulators.
[color=blue]
> }else{
> printf("%s%d\n" ,n ? "-":"",v);[/color]
The ternary operator ?: can make for unreadable code. Better to use
it sparingly. If you do use it then put spaces round both the '?' and
the ':' for clarity. Again spaces after any commas that separate
parameters are easier to read.

Are you really sure about that '\n' there? I hope that you
cut-and-pasted this rather than typed it from scratch.
[color=blue]
> }
>}
>
>void display_number( int v){
> _display_number (v < 0 ? -v : v,v < 0);[/color]
Where the ternary operator has a boolean expression it is better to
put the expression in brackets: (v < 0) ? -v : v to improve
readability. Again put a space after the parameter separating comma.[color=blue]
>}
>
>int main(int argc,char** argv){
> display_number( 35000);
> display_number( 600);
> display_number( 8765);
> display_number( 120000);
> display_number( 3800000);
> display_number(-3800000);[/color]

Main does not require a return value, but it is better style to
include it explicitly. I tend to use the EXIT_SUCCESS and
EXIT_FAILURE macros.
[color=blue]
>}
>
>The program prints something like:
>
>35,000
>600
>8,765
>120,000
>3,800,000
>-3,800,000
>
>HTH. I am here to learn as well so if anyone can help me improve the
>program, I am happy to see it. Thanks![/color]

Hope you find that useful.

rossum


--

The Ultimate Truth is that there is no Ultimate Truth