some tricky questions

[birensubudhi]

1) void foo(char *s,char *t)
{
while(*s++=*t++ );
}

which C function is equivalent to foo ?

2) #define ROUND(x,n)

((x+n-1)&(~(n-1)))
what is hte value of ROUND(223,64) ?
DESCRIBE IT HOW IT IS SO?

3) void foo(int x)
{
int i=0;
while(x)
{
x=x&(x-1);
i++;
}
printf("%d",i);
}
what is the o/p of this function & why it is so ?
what function does this '&' does ?
4) union{
int i;
char c[sizeof(int)];
}x;
x.i=1;
if(x.c[0]==1)
printf("the m/c is _______________ endian");
else
printf("the m/c is _______________ endian");

fill in the blanks with tthe correct option:
a) little,big b)big,big
c) big,little d)little,little

5) int fun2(char *a,char *b)
{
for(; *a==*b;a++,b++)
if(*a=='\0')
return 0;

return *a-*b;
}
char a[10]="date",b[10]="data";

what is the value of fun2(a,b)?

[Tor Rustad]

bi**********@gm ail.com wrote:

1) void foo(char *s,char *t)
{
while(*s++=*t++ );
}

which C function is equivalent to foo ?

FYI, we don't do homework.

--
Tor <torust [at] online [dot] no>

[Army1987]

<bi**********@g mail.comha scritto nel messaggio
news:11******** **************@ n15g2000prd.goo glegroups.com.. .

1) void foo(char *s,char *t)
{
while(*s++=*t++ );
}

which C function is equivalent to foo ?

None. strcpy returns a char* equal to its first argument. Also, the
second argument of strcpy is a const char*.

2) #define ROUND(x,n)

((x+n-1)&(~(n-1)))
what is hte value of ROUND(223,64) ?
DESCRIBE IT HOW IT IS SO?

It is the value of ((223+64-1)&(~(64-1))), of course.

3) void foo(int x)
{
int i=0;
while(x)
{
x=x&(x-1);
i++;
}
printf("%d",i);
}
what is the o/p of this function & why it is so ?
what function does this '&' does ?

If x is INT_MIN, it is allowed to make demons fly out of your nose.
BTW, what is an o/p? And the '&' does no "function", at least in the C
sense.

4) union{
int i;
char c[sizeof(int)];
}x;
x.i=1;
if(x.c[0]==1)
printf("the m/c is _______________ endian");
else
printf("the m/c is _______________ endian");

fill in the blanks with tthe correct option:
a) little,big b)big,big
c) big,little d)little,little

Nope. It could be middle endian. And if I'm not wrong, the standard
specifies nothing about the bit order. On a conforming implementation, it
could be sizeof (int) == 2 && CHAR_BIT ==8, and
the first byte of i could contain the first, third, fifth, seventh,
ninth, eleventh, thirteenth, and fifteenth bit in that order, and
the second byte could contain the sixteenth, fourteenth, ..., second bit in
that order.

5) int fun2(char *a,char *b)
{
for(; *a==*b;a++,b++)
if(*a=='\0')
return 0;

return *a-*b;
}
char a[10]="date",b[10]="data";

what is the value of fun2(a,b)?

It is 'e' - 'a', which nothing requires to be four. It could be
anything from CHAR_MIN - CHAR_MAX to -1 included, and it could be
anything from 1 to CHAR_MAX - CHAR_MIN included. Not all the world
uses ASCII.

[per9000]

On Jun 2, 12:28 pm, "Army1987" <please....@for .itwrote:

<birensubu...@g mail.comha scritto nel messaggionews:1 1************** ********@n15g20 00prd.googlegro ups.com...

[...]

2) #define ROUND(x,n)

((x+n-1)&(~(n-1)))
what is hte value of ROUND(223,64) ?
DESCRIBE IT HOW IT IS SO?

It is the value of ((223+64-1)&(~(64-1))), of course.
[...]

The reason: "by definition".
[:)]-|--<

/Per

--

Per Erik Strandberg
home: www.pererikstrandberg.se
work: www.incf.org
also: www.spongswedencare.se

[Kenny McCormack]

In article <11************ **********@n15g 2000prd.googleg roups.com>,
<bi**********@g mail.comwrote:

>1) void foo(char *s,char *t)
{
while(*s++=*t++ );
}

which C function is equivalent to foo ?

What is homework, Alex?

[Keith Thompson]

bi**********@gm ail.com writes:

1) void foo(char *s,char *t)
{
while(*s++=*t++ );
}

which C function is equivalent to foo ?

foo.

--
Keith Thompson (The_Other_Keit h) ks***@mib.org <http://www.ghoti.net/~kst>
San Diego Supercomputer Center <* <http://users.sdsc.edu/~kst>
"We must do something. This is something. Therefore, we must do this."
-- Antony Jay and Jonathan Lynn, "Yes Minister"

[Robert Gamble]

On Jun 2, 6:28 am, "Army1987" <please....@for .itwrote:

<birensubu...@g mail.comha scritto nel messaggionews:1 1************** ********@n15g20 00prd.googlegro ups.com...

1) void foo(char *s,char *t)
{
while(*s++=*t++ );

}

which C function is equivalent to foo ?

None. strcpy returns a char* equal to its first argument. Also, the
second argument of strcpy is a const char*.

2) #define ROUND(x,n)

((x+n-1)&(~(n-1)))
what is hte value of ROUND(223,64) ?
DESCRIBE IT HOW IT IS SO?

It is the value of ((223+64-1)&(~(64-1))), of course.

3) void foo(int x)
{
int i=0;
while(x)
{
x=x&(x-1);
i++;
}
printf("%d",i);
}
what is the o/p of this function & why it is so ?
what function does this '&' does ?

If x is INT_MIN, it is allowed to make demons fly out of your nose.
BTW, what is an o/p? And the '&' does no "function", at least in the C
sense.

4) union{
int i;
char c[sizeof(int)];
}x;
x.i=1;
if(x.c[0]==1)
printf("the m/c is _______________ endian");
else
printf("the m/c is _______________ endian");

fill in the blanks with tthe correct option:
a) little,big b)big,big
c) big,little d)little,little

Nope. It could be middle endian.

Right.

And if I'm not wrong, the standard
specifies nothing about the bit order. On a conforming implementation, it
could be sizeof (int) == 2 && CHAR_BIT ==8, and
the first byte of i could contain the first, third, fifth, seventh,
ninth, eleventh, thirteenth, and fifteenth bit in that order, and
the second byte could contain the sixteenth, fourteenth, ..., second bit in
that order.

Thankfully you are wrong about this, see 9899:1999 section 6.2.6.2.

Robert Gamble

[Richard]

Tor Rustad <to********@hot mail.comwrites:

bi**********@gm ail.com wrote:

>1) void foo(char *s,char *t)
{
while(*s++=*t++ );
}

which C function is equivalent to foo ?

FYI, we don't do homework.

Who is "we"? Because someone else did.

[Mark McIntyre]

On Sun, 03 Jun 2007 00:12:06 +0200, in comp.lang.c , Richard
<rg****@gmail.c omwrote:

>Tor Rustad <to********@hot mail.comwrites:

>bi**********@gm ail.com wrote:

>>1) void foo(char *s,char *t)
{
while(*s++=*t++ );
}

which C function is equivalent to foo ?

FYI, we don't do homework.

Who is "we"? Because someone else did.

Did'ja read the answers? Not entirely likely to pass the homework
test...

--
Mark McIntyre

"Debugging is twice as hard as writing the code in the first place.
Therefore, if you write the code as cleverly as possible, you are,
by definition, not smart enough to debug it."
--Brian Kernighan

[Tor Rustad]

Richard wrote:

Tor Rustad <to********@hot mail.comwrites:

[...]

>FYI, we don't do homework.

Who is "we"? Because someone else did.

I exclude spammers, and that someone else was spamming in my view.
--
Tor <torust [at] online [dot] no>