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Mail Archives: djgpp/1999/03/14/15:10:58

From: "Ron Higgins" <ron AT west29 DOT freeserve DOT co DOT uk DOT nospam>
Newsgroups: comp.os.msdos.djgpp
Subject: Newbie Pointers
Date: Sun, 14 Mar 1999 19:27:13 -0000
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The Exercise

Define a character array and use "strcpy" to copy a string into it.  Print
the string out by using a loop with a pointer to print out one character at
a time.

Initialise the pointer to the first element and use the double plus sign to
increment the pointer.  Use a seperate integer variable to count the
characters to print.

b) Modify the program to print out the string backwards by pointing to the
end and using a decrementing pointer.


After a time getting CRAZY I decided to do it just using arrays and came up
with this ,

main()
{
static char ar1[16];
char *ptr1;  /* this was from my attempt using pointers, ignore */
int count;

strcpy(ar1,"This is a string");


for (count=0;count<16;count++) {
printf("%c\n",ar1[count]);
}

for (count=15;count>-1;count--) {
printf("%c\n",ar1[count]);
}
}
which would be fine if the exercise didn't mention pointers :(

my mind is going along the lines :     ptr1=ar1;
                                                         while (ptr1
!=0(???))
                                                        printf("%c\n",ptr1);
                                                        ptr++;

but this list lots of ascii characters

                                                b) ptr1=ar1[15]
                                                    while (ptr1
!=something???)
                                                    printf("%c\n",ptr);
                                                    ptr--;

I don't know whether I am miles away or close to solving the problem
--
L8ter, Ron


--
L8ter, Ron


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