Homework help

MacGyver · 07-04-2008, 05:51 AM

Quote:

Originally Posted by @nthony

requesting obligatory posting of mac's signature and lock... in that order.

You rang, sir?

azerej · 07-04-2008, 07:03 PM

2. Be able to demonstrate and explain programs to your lecturer.

Even if we create the code for you, do you think you can able to explain it?

mkdl750 · 07-07-2008, 01:18 AM

Okay I'm done with subquestions A, B, C, D, and I really don't understand what memory diagrams are. I am asked to trace the following C program and write down its output. Can you kindly assist me in this one?

Code:

#include <stdio.h>
#include <conio.h>

char *B1, *B2, *B3, *B4, *B5;
char BLUR[8] = {'M', 'O', 'R', 'E', 'B', 'L', 'U', 'R'};

main()
{
clrscr();
B5=B4=BLUR;
++B4;
B3=&BLUR[6];
B2=B5+2;
B1=&BLUR[7]-3;

printf ("%c\t%c\t%c\t%c\t%c",*B1,*B2,*B3,*B4,*B5);

getch();
return 0;
}

vlrk · 07-07-2008, 03:30 AM

B5=B4=BLUR

1) B5 and B4 are pointers to characters

2) BLUR = BLUR[0]

I think that above two points will help you to calcuate the output.

vart · 07-07-2008, 03:41 AM

Quote:

BLUR = BLUR[0]

not exactly

Code:

 BLUR == &BLUR[0]

shwetha_siddu · 07-07-2008, 04:49 AM

Quote:

Originally Posted by mkdl750

Okay I'm done with subquestions A, B, C, D, and I really don't understand what memory diagrams are. I am asked to trace the following C program and write down its output. Can you kindly assist me in this one?

Code:

#include <stdio.h>
#include <conio.h>

char *B1, *B2, *B3, *B4, *B5;
char BLUR[8] = {'M', 'O', 'R', 'E', 'B', 'L', 'U', 'R'};

main()
{
clrscr();
B5=B4=BLUR;
++B4;
B3=&BLUR[6];
B2=B5+2;
B1=&BLUR[7]-3;

printf ("%c\t%c\t%c\t%c\t%c",*B1,*B2,*B3,*B4,*B5);

getch();
return 0;
}

The output of following program is :- B R U O M

Code:

#include <stdio.h>
#include <conio.h> 
char *B1, *B2, *B3, *B4, *B5;
char BLUR[8] = {'M', 'O', 'R', 'E', 'B', 'L', 'U', 'R'};

int main()
{
B5=B4=BLUR;//Both Pointers are assigned to 'M' 
++B4;  //Now it will point to 'O'
B3=&BLUR[6]; //'U' has been assigned
B2=B5+2; //'R' has been assigned
B1=&BLUR[7]-3; //'B' has been assigned

printf ("%c\t%c\t%c\t%c\t%c",*B1,*B2,*B3,*B4,*B5); //B  R  U  O  M

getch();
return 0;
}

mkdl750 · 07-08-2008, 04:51 AM

Okay now please show the memory diagram in subquestion L.

zacs7 · 07-08-2008, 04:53 AM

> Okay now please show the memory diagram in subquestion L.
Negative. http://pages.cs.wisc.edu/~cs302/reso..._diagrams.html

mkdl750 · 07-10-2008, 08:01 PM

Heres my draft solution for subquestion E.

Code:

#include <stdio.h>
#include <string.h>

int CountEvenASCII(char *str);

main()
{
char *x[20];
printf("Enter a string of letters: ");
scanf("%c",x);
CountEvenASCII(*x);
printf("%d",CountEvenASCII(*x));
getch();
return 0;
}

int CountEvenASCII(char *str)
{
 if(str[0] == '\0')
	return 0;
 if((int)str[0] % 2 == 0)
	return 1 + CountEvenASCII(str + 1);
 else
	return CountEvenASCII(str + 1);
}

But how can I display the number of letters with even ASCII character values?

MacGyver · 07-10-2008, 09:47 PM

That code is horrible. If someone taught you to write that, they did you a disservice.....

mkdl750 · 07-11-2008, 12:56 AM

any further assistance about my answer to subquestion E?

tabstop · 07-11-2008, 10:34 AM

There is no such thing as "main()". There is "int main()", and there is "int main(int argc, char *argv[])".
Indentation is something you should look into. Basically: everything inside curly braces should be moved over by the same amount (and the more braces, the further over you go).
A string (which should probably not be called "x") can be either char *x, or char x[20], but not both. The declaration char *x[20] gives you 20 pointers-to-characters; each pointer-to-character could be a string one day, if you malloc'ed memory for those pointers to point to.
%c only reads one character from standard input. %s will read in a string, provided it has no spaces, but needs work to be safe. There is such a thing as fgets.
There's no need to call the function twice -- once inside the print statement should be sufficient.

abachler · 07-11-2008, 10:53 AM

Code:

 
char Dec(char a){
   return 64 + (((63 & a)+ 1) % 26);
   }

do I win a cookie ?

mkdl750 · 07-13-2008, 07:04 PM

Can you help me correct this code?

Code:

#include <stdio.h>
#include <string.h>

int CountEvenASCII(char *str);

main()
{
char *x[20];
printf("Enter a string of letters: ");
scanf("%c",x);
CountEvenASCII(*x);
printf("%d",CountEvenASCII(*x));
getch();
return 0;
}

int CountEvenASCII(char *str)
{
 if(str[0] == '\0')
	return 0;
 if((int)str[0] % 2 == 0)
	return 1 + CountEvenASCII(str + 1);
 else
	return CountEvenASCII(str + 1);
}

eXeCuTeR · 07-13-2008, 07:17 PM

Quote:

Originally Posted by mkdl750

Can you help me correct this code?

Code:

#include <stdio.h>
#include <string.h>

int CountEvenASCII(char *str);

main()
{
char *x[20];
printf("Enter a string of letters: ");
scanf("%c",x);
CountEvenASCII(*x);
printf("%d",CountEvenASCII(*x));
getch();
return 0;
}

int CountEvenASCII(char *str)
{
 if(str[0] == '\0')
	return 0;
 if((int)str[0] % 2 == 0)
	return 1 + CountEvenASCII(str + 1);
 else
	return CountEvenASCII(str + 1);
}

Your algorithm is correct but the way you are calling it is wrong.
This should be done just like the following (check out the changes in CountEvenASCII)

Code:

int CountEvenASCII(const char *str) // since you are not making any changes to the string, it's supposed to be a constant string.
{
 if(str[0] == '\0')
	return 0;
 if((int)str[0] % 2 == 0)
	return 1 + CountEvenASCII(str + 1);
 return CountEvenASCII(str + 1); // no 'else' is needed.
}

int main(void)
{
    const char *abc = "AB";
    printf("%d", CountEvenASCII(abc));
    return 0;   
}

07-04-2008, 07:03 PM	#17
azerej Registered User Join Date: May 2008 Posts: 12	2. Be able to demonstrate and explain programs to your lecturer. Even if we create the code for you, do you think you can able to explain it?
azerej is offline

07-07-2008, 01:18 AM	#18
mkdl750 Registered User Join Date: Jul 2008 Posts: 38	I dont really understand subquestion L Okay I'm done with subquestions A, B, C, D, and I really don't understand what memory diagrams are. I am asked to trace the following C program and write down its output. Can you kindly assist me in this one? Code: #include <stdio.h> #include <conio.h> char B1, B2, B3, B4, B5; char BLUR[8] = {'M', 'O', 'R', 'E', 'B', 'L', 'U', 'R'}; main() { clrscr(); B5=B4=BLUR; ++B4; B3=&BLUR[6]; B2=B5+2; B1=&BLUR[7]-3; printf ("%c\t%c\t%c\t%c\t%c",B1,B2,B3,B4,B5); getch(); return 0; }
mkdl750 is offline

07-07-2008, 03:30 AM	#19
vlrk Registered User Join Date: Mar 2008 Location: India Posts: 70	B5=B4=BLUR 1) B5 and B4 are pointers to characters 2) BLUR = BLUR[0] I think that above two points will help you to calcuate the output.
vlrk is offline

07-08-2008, 04:51 AM	#22
mkdl750 Registered User Join Date: Jul 2008 Posts: 38	Okay now please show the memory diagram in subquestion L.
mkdl750 is offline

07-08-2008, 04:53 AM	#23
zacs7 Woof, woof! Join Date: Mar 2007 Location: Australia Posts: 3,139	> Okay now please show the memory diagram in subquestion L. Negative. http://pages.cs.wisc.edu/~cs302/reso..._diagrams.html __________________ "I.T. gets the chicky-babes" - M. Kelly bakefile \| vim
zacs7 is offline

07-10-2008, 09:47 PM	#25
MacGyver Deathray Engineer Join Date: Mar 2007 Posts: 3,211	That code is horrible. If someone taught you to write that, they did you a disservice..... __________________
MacGyver is offline

07-11-2008, 12:56 AM	#26
mkdl750 Registered User Join Date: Jul 2008 Posts: 38	any further assistance about my answer to subquestion E?
mkdl750 is offline

07-11-2008, 10:34 AM	#27
tabstop and the Hat of Guessing Join Date: Nov 2007 Posts: 8,740	There is no such thing as "main()". There is "int main()", and there is "int main(int argc, char argv[])". Indentation is something you should look into. Basically: everything inside curly braces should be moved over by the same amount (and the more braces, the further over you go). A string (which should probably not be called "x") can be either char x, or char x[20], but not both. The declaration char *x[20] gives you 20 pointers-to-characters; each pointer-to-character could be a string one day, if you malloc'ed memory for those pointers to point to. %c only reads one character from standard input. %s will read in a string, provided it has no spaces, but needs work to be safe. There is such a thing as fgets. There's no need to call the function twice -- once inside the print statement should be sufficient.
tabstop is offline

07-11-2008, 10:53 AM	#28
abachler Rampaging 35 Stone Welsh Join Date: Apr 2007 Posts: 2,927	Code: char Dec(char a){ return 64 + (((63 & a)+ 1) % 26); } do I win a cookie ? __________________ He is free, you say. Ah! That is his misfortune… These men… [have] the most terrible, the most imperious of masters, that is, need. … They must therefore find someone to hire them, or die of hunger. Is that to be free? - Simon Linguet Last edited by abachler; 07-11-2008 at 10:56 AM.
abachler is offline

Thread Tools
Show Printable Version Email this Page
Display Modes
Linear Mode Switch to Hybrid Mode Switch to Threaded Mode

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
Homework	kermi3	A Brief History of Cprogramming.com	11	11-03-2001 04:39 PM
Homework	kermi3	C Programming	10	09-27-2001 04:49 PM
Homework	kermi3	C++ Programming	15	09-26-2001 03:16 PM
Homework	kermi3	Windows Programming	5	09-15-2001 11:48 AM
Homework	kermi3	C Programming	0	09-10-2001 01:26 PM