Keyser Soze wrote:

So,
please can you experts just do the work for me and not whine about how
lazy and dishonest I am.

I like to do other people's homework
if it's interesting and not too hard.
I'm one of the dangerous people on USENET
that your mother warned you about.

mensanator@aol.com said:

Default User wrote:
>pete wrote:
>>
>>
>I like to do other people's homework
>if it's interesting and not too hard.
>I'm one of the dangerous people on USENET
>that your mother warned you about.
>>
>Worst poem ever.
>
A likeable fellow called P_
Posts homework from others for free.
It won't be undone
As long as it's fun,
But that's no way to get your degree.

Cheating novices
Teach ancient gurus to dread
Endless September.

In article <43977DC7.6591@mindspring.com>,
pete <pfiland@mindspring.comwrote:
>Keyser Soze wrote:
>
>So,
>please can you experts just do the work for me and not whine about how
>lazy and dishonest I am.
>
>I like to do other people's homework
>if it's interesting and not too hard.

I do too. This is one of my favorites:

#include <stdio.h>
#include <stdlib.h>

typedef struct n{struct n*p1,*p2;int v;}n;n*r_t(n*p,n*i){n*i2,*t1,*t2;int v
;if(!i)return 0;while(p->p2)p=p->p2;i2=i;do{t1=malloc(sizeof*t1);t2=malloc(
sizeof*t2);if(!t1||!t2)return 0;t1->v=t2->v=i2->v;t2->p1=t2->p2=0;t1->p1=i2
;t1->p2=t2;if(t1->p1->p2)t1->p1->p2->p1=t1;if(t1->p1->p1)t1->p1->p1->p1->p2
=t1;i2=t1->p1->p2;}while(i2);i=t1;while(i->p1->p1){i2=i;v=i2->v;while(p->v!=
v&&p->p1->v!=v){i2=i2->p1->p1;if(!i2){fputs("(1)\n",stderr);return 0;}v=i2
->v;}if(v==p->v){if(p->p1){p=p->p1;free(p->p2);p->p2=0;}else{fputs("(2)\n",
stderr);return 0;}if(i2->p1->p1)i2->p1->p1->p1->p2=i2->p1->p2;if(i2->p1->p2
)i2->p1->p2->p1->p1=i2->p1->p1;else i=i2;t1=i2->p2;t2=i2->p1->p1;free(i2->
p1);free(i2);t2->p2->p2=t1;}else{t2=p->p1;if(t2->p1)t2->p1->p2=t2->p2;t2->p2
->p1=t1->p1;free(t2);i2=i2->p1->p1;if(i2->p1->p1)i2->p1->p1->p1->p2=i2->p1->
p2;i2->p1->p2->p1->p1=i2->p1->p1;t1=i2->p2;t2=i2->p1->p2;free(i2->p1);free(
i2);t2->p2->p1=t1;}}if(p->p1||p->p2)fputs("(3)\n",stderr);free(p);if(i->p1->
p1||i->p1->p2)fputs("(4)\n",stderr);t1=i->p2;free(i->p1);free(i);return t1;}


>I'm one of the dangerous people on USENET
>that your mother warned you about.

I'm an entirely different kind of dangerous people on USENET, the kind
your mother never thought you'd need to be warned about.

dave
(I remember that there was a bug in my first version of that one. I have
no idea whether it's been fixed in the version I have laying around.)

In article <86y82vexcg.fsf@xps.des.no>, Dag-Erling Smrgrav <des@des.nowrote:
>dj3vande@csclub.uwaterloo.ca (Dave Vandervies) writes:
>#include <stdio.h>
>#include <stdlib.h>
>>
>typedef struct n{struct n*p1,*p2;int v;}n;n*r_t(n*p,n*i){n*i2,*t1,*t2;int v
>;if(!i)return 0;while(p->p2)p=p->p2;i2=i;do{t1=malloc(sizeof*t1);t2=malloc(
>sizeof*t2);if(!t1||!t2)return 0;t1->v=t2->v=i2->v;t2->p1=t2->p2=0;t1->p1=i2
>;t1->p2=t2;if(t1->p1->p2)t1->p1->p2->p1=t1;if(t1->p1->p1)t1->p1->p1->p1->p2
>=t1;i2=t1->p1->p2;}while(i2);i=t1;while(i->p1->p1){i2=i;v=i2->v;while(p->v!=
>v&&p->p1->v!=v){i2=i2->p1->p1;if(!i2){fputs("(1)\n",stderr);return 0;}v=i2
>->v;}if(v==p->v){if(p->p1){p=p->p1;free(p->p2);p->p2=0;}else{fputs("(2)\n",
>stderr);return 0;}if(i2->p1->p1)i2->p1->p1->p1->p2=i2->p1->p2;if(i2->p1->p2
>)i2->p1->p2->p1->p1=i2->p1->p1;else i=i2;t1=i2->p2;t2=i2->p1->p1;free(i2->
>p1);free(i2);t2->p2->p2=t1;}else{t2=p->p1;if(t2->p1)t2->p1->p2=t2->p2;t2->p2
>->p1=t1->p1;free(t2);i2=i2->p1->p1;if(i2->p1->p1)i2->p1->p1->p1->p2=i2->p1->
>p2;i2->p1->p2->p1->p1=i2->p1->p1;t1=i2->p2;t2=i2->p1->p2;free(i2->p1);free(
>i2);t2->p2->p1=t1;}}if(p->p1||p->p2)fputs("(3)\n",stderr);free(p);if(i->p1->
>p1||i->p1->p2)fputs("(4)\n",stderr);t1=i->p2;free(i->p1);free(i);return t1;}
>
>But what if p is NULL?

Hmm, I should have checked for that as well. Good catch.
If it happens when i!=NULL, though, it means the input is malformed (p and
i are supposed to be different representations of the same data) and it
could reasonably be argued that the input disagrees with the specification
and there's no requirement that the code does something sensible with it.

dave

In article <1134038549.136080.74630@g49g2000cwa.googlegroups.c om>,
Suman <skarpio@gmail.comwrote:
>
>Dave Vandervies wrote:
>[]
>This is one of my favorites:
>
>#include <stdio.h>
>#include <stdlib.h>
>>
>typedef struct n{struct n*p1,*p2;int v;}n;n*r_t(n*p,n*i){n*i2,*t1,*t2;int v
>;if(!i)return 0;while(p->p2)p=p->p2;i2=i;do{t1=malloc(sizeof*t1);t2=malloc(
>sizeof*t2);if(!t1||!t2)return 0;t1->v=t2->v=i2->v;t2->p1=t2->p2=0;t1->p1=i2
>;t1->p2=t2;if(t1->p1->p2)t1->p1->p2->p1=t1;if(t1->p1->p1)t1->p1->p1->p1->p2
>=t1;i2=t1->p1->p2;}while(i2);i=t1;while(i->p1->p1){i2=i;v=i2->v;while(p->v!=
>v&&p->p1->v!=v){i2=i2->p1->p1;if(!i2){fputs("(1)\n",stderr);return 0;}v=i2
>->v;}if(v==p->v){if(p->p1){p=p->p1;free(p->p2);p->p2=0;}else{fputs("(2)\n",
>stderr);return 0;}if(i2->p1->p1)i2->p1->p1->p1->p2=i2->p1->p2;if(i2->p1->p2
>)i2->p1->p2->p1->p1=i2->p1->p1;else i=i2;t1=i2->p2;t2=i2->p1->p1;free(i2->
>p1);free(i2);t2->p2->p2=t1;}else{t2=p->p1;if(t2->p1)t2->p1->p2=t2->p2;t2->p2
>->p1=t1->p1;free(t2);i2=i2->p1->p1;if(i2->p1->p1)i2->p1->p1->p1->p2=i2->p1->
>p2;i2->p1->p2->p1->p1=i2->p1->p1;t1=i2->p2;t2=i2->p1->p2;free(i2->p1);free(
>i2);t2->p2->p1=t1;}}if(p->p1||p->p2)fputs("(3)\n",stderr);free(p);if(i->p1->
>p1||i->p1->p2)fputs("(4)\n",stderr);t1=i->p2;free(i->p1);free(i);return t1;}
>
>
>1. main() would have been most welcome :)

int main(void)
{
if(r_t(0,0))
{
fputs("Error: Bad handling of trivial input\n",stderr);
return EXIT_FAILURE;
}
return EXIT_SUCCESS;
}

But, seriously: it wasn't part of the specification I was working from
when I wrote it, so it didn't make it in.
I'll see if I can find some of my Copious Free Time later this week to
write a decent test driver. (My first attempt failed, and I suspect it
may be because this version didn't correct the bug I found in my first
attempt at it. So I may also end up correcting the code I posted.)

>2. what if we have something like:
>n node1 = { NULL, NULL, 1 };n node2 = { NULL, NULL, 2 };n node = {
>NULL, NULL, 3 };
>node.p1 = &node2;node.p2 = &node1;node1.p1 = &node;node1.p2 = &node2;
>node2.p1 = &node1;node2.p2 = &node;
>
>Is the above input well (-enough, for the above, that is) formed?

No. Cycles aren't allowed.

dave