HELP!! Two questions from <<the c programming language>>

[Tak]

Exercise 1-9. Write a program to copy its input to its output,
replacing each string of one or
more blanks by a single blank.

Exercise 1-10. Write a program to copy its input to its output,
replacing each tab by \t, each
backspace by \b, and each backslash by \\. This makes tabs and
backspaces visible in an
unambiguous way.

Who could sent me the codes, Thanks very much! My email:
ka******@gmail. com

[Chris Dollin]

Guru Jois wrote:

A bunch of not-C, for no terribly good reason but:

while EOF

I don't think so.

do
begin
input char
if char = space then
begin
if flag = 0 then

No declaration for `flag`; hence, no know state.

begin
let flag = 1;
print char;
end
end
else
begin
let flag = 0
print char
end
end
goto step 2

You have no step 2 (in fact you have no steps).

You don't need `goto` for this problem, especially if you're
going to write in an invented pseudocode.

end while

Make up your mind whether you're using begin-end blocks or
whether your control-structures have end-Whatever syntax.

--
"He's dead, Jim, but not as we know it." Unsaid /Trek/

Hewlett-Packard Limited Cain Road, Bracknell, registered no:
registered office: Berks RG12 1HN 690597 England

[Guru Jois]

On May 31, 2:24 pm, Chris Dollin <chris.dol...@h p.comwrote:

Guru Jois wrote:

A bunch of not-C, for no terribly good reason but:

while EOF

I don't think so.

do
begin
input char
if char = space then
begin
if flag = 0 then

No declaration for `flag`; hence, no know state.

begin
let flag = 1;
print char;
end
end
else
begin
let flag = 0
print char
end
end
goto step 2

You have no step 2 (in fact you have no steps).

You don't need `goto` for this problem, especially if you're
going to write in an invented pseudocode.

end while

Make up your mind whether you're using begin-end blocks or
whether your control-structures have end-Whatever syntax.

--
"He's dead, Jim, but not as we know it." Unsaid /Trek/

Hewlett-Packard Limited Cain Road, Bracknell, registered no:
registered office: Berks RG12 1HN 690597 England

just a steps to that asker... sir. I wrote it as steps, but later
removed, but forget this one....
Please identify notable mistakes...not a silly ones

Bye
Guru Jois

[Tak]

Algorithm trim_space

>
while EOF
do
begin
input char
if char = space then
begin
if flag = 0 then
begin
let flag = 1;
print char;
end
end
else
begin
let flag = 0
print char
end
end
goto step 2
end while

My program of exercise 1-9

#include <stdio.h>

int main()
{
int flag=1;
int c;

while ((c = getchar()) != EOF)
{
if (c == ' ')
{
flag = 0;
}
else if (flag == 0)
{
printf(" ");
putchar(c);
flag = 1;
}
else
putchar(c);
}
}

It seems run OK,without error or warning in Vc++6.0.
Does it still contain any problems?

[Chris Dollin]

Guru Jois wrote:

On May 31, 2:24 pm, Chris Dollin <chris.dol...@h p.comwrote:

>Guru Jois wrote:

A bunch of not-C, for no terribly good reason but:

SNIP SIGNATURES.

just a steps to that asker... sir. I wrote it as steps, but later
removed, but forget this one....
Please identify notable mistakes...not a silly ones

(a) I did. The very first line is a notable mistake, rendering the
algorithm useless:

while EOF

(b) Computers can't tell the difference between a silly mistake and
a notable one.

(c) Programmers have to take care /all the time/. Sloppiness feeds
on itself.

--
"It is seldom good news." ~Crystal Ball~, /The Tough Guide to Fantasyland/

Hewlett-Packard Limited registered no:
registered office: Cain Road, Bracknell, Berks RG12 1HN 690597 England

[Ben Bacarisse]

Tak <ka******@gmail .comwrites:

>Algorithm trim_space

<bad algorithm snipped>

>
My program of exercise 1-9

#include <stdio.h>

int main()
{
int flag=1;
int c;

while ((c = getchar()) != EOF)
{
if (c == ' ')
{
flag = 0;
}
else if (flag == 0)
{
printf(" ");
putchar(c);
flag = 1;
}
else
putchar(c);
}
}

It seems run OK,without error or warning in Vc++6.0.
Does it still contain any problems?

Yes. What happens when the input ends with one or more spaces?

--
Ben.

[CBFalconer]

Tak wrote:

>
I know how to do, Thank you!

How to do what? Read the following sig.

--
If you want to post a followup via groups.google.c om, ensure
you quote enough for the article to make sense. Google is only
an interface to Usenet; it's not Usenet itself. Don't assume
your readers can, or ever will, see any previous articles.
More details at: <http://cfaj.freeshell. org/google/>

--
Posted via a free Usenet account from http://www.teranews.com

[Guru Jois]

On May 31, 6:04 pm, Ben Bacarisse <ben.use...@bsb .me.ukwrote:

Tak <kakat...@gmail .comwrites:

Algorithm trim_space

<bad algorithm snipped>

My program of exercise 1-9

#include <stdio.h>

int main()
{
int flag=1;
int c;

while ((c = getchar()) != EOF)
{
if (c == ' ')
{
flag = 0;
}
else if (flag == 0)
{
printf(" ");
putchar(c);
flag = 1;
}
else
putchar(c);
}
}

It seems run OK,without error or warning in Vc++6.0.
Does it still contain any problems?

Yes. What happens when the input ends with one or more spaces?

--
Ben.

yet smaller code..

#include<stdio. h>
main() {

int c;
int flag;

flag = 0;

while ((c = getchar ()) != EOF) {
if (c == ' ') {
if (!flag) {
flag = 1;
putchar (c);
}
}
else {
flag = 0;
putchar (c);
}
}

}

Bye
Guru Jois

[Guru Jois]

On May 31, 3:27 pm, Tak <kakat...@gmail .comwrote:

Algorithm trim_space

while EOF
do
begin
input char
if char = space then
begin
if flag = 0 then
begin
let flag = 1;
print char;
end
end
else
begin
let flag = 0
print char
end
end
goto step 2
end while

My program of exercise 1-9

#include <stdio.h>

int main()
{
int flag=1;
int c;

while ((c = getchar()) != EOF)
{
if (c == ' ')
{
flag = 0;
}
else if (flag == 0)
{
printf(" ");
putchar(c);
flag = 1;
}
else
putchar(c);
}

}

It seems run OK,without error or warning in Vc++6.0.
Does it still contain any problems?

yet smaller code..

#include<stdio. h>
main() {

int c;
int flag;

flag = 0;

while ((c = getchar ()) != EOF) {
if (c == ' ') {
if (!flag) {
flag = 1;
putchar (c);
}
}
else {
flag = 0;
putchar (c);
}
}

}

Bye
Guru Jois

[Ben Bacarisse]

Guru Jois <gu*******@gmai l.comwrites:

On May 31, 6:04 pm, Ben Bacarisse <ben.use...@bsb .me.ukwrote:

>Tak <kakat...@gmail .comwrites:

>Algorithm trim_space

<bad algorithm snipped>

>>

My program of exercise 1-9

#include <stdio.h>

int main()
{

<snipped>

}

It seems run OK,without error or warning in Vc++6.0.
Does it still contain any problems?

Yes. What happens when the input ends with one or more spaces?

yet smaller code..

#include<stdio. h>
main() {

int c;
int flag;

flag = 0;

while ((c = getchar ()) != EOF) {
if (c == ' ') {
if (!flag) {
flag = 1;
putchar (c);
}
}
else {
flag = 0;
putchar (c);
}
}

}

I'd write it:

#include <stdio.h>

int main(void)
{
int c;
char last_char = '\n'; /* Anything that is not a space */
while ((c = getchar()) != EOF) {
if (c != ' ' || last_char != ' ')
putchar(c);
last_char = c;
}
return 0;
}

because I am not a fan of flag variables and this pattern is very
useful for all sorts of filtering and counting programs.

--
Ben.

[Guru Jois]

On May 31, 6:04 pm, Ben Bacarisse <ben.use...@bsb .me.ukwrote:

Tak <kakat...@gmail .comwrites:

Algorithm trim_space

<bad algorithm snipped>

My program of exercise 1-9

#include <stdio.h>

int main()
{
int flag=1;
int c;

while ((c = getchar()) != EOF)
{
if (c == ' ')
{
flag = 0;
}
else if (flag == 0)
{
printf(" ");
putchar(c);
flag = 1;
}
else
putchar(c);
}
}

It seems run OK,without error or warning in Vc++6.0.
Does it still contain any problems?

Yes. What happens when the input ends with one or more spaces?

--
Ben.

yet smaller code..

#include<stdio. h>
main() {

int c;
int flag;

flag = 0;

while ((c = getchar ()) != EOF) {
if (c == ' ') {
if (!flag) {
flag = 1;
putchar (c);
}
}
else {
flag = 0;
putchar (c);
}
}

}

Bye
Guru Jois