scanf and Malloc Help

[OOzy]

How can I prompt the user to enter two strings then concatenates the two strings and use the malloc() function to allocate enough memory to hold the two strings after they have been concatenated.
Then return a pointer to this new string.

For example, if I pass "hello " and "world!", the function returns a pointer to "Hello world!".

 

[rbobbitt]

Use fgets() to get the strings from the user, storing each string in a separate array of char (scanf() can be used too, but fgets() is much better suited for grabbing strings from the user).

Pass the strings to your "concatenation" function

Use strlen() in the function to compute the length of each string and add the lengths together.

Use malloc() to allocate memory based on the total lengths of the strings + 2 (for the terminating null and the space between the strings).

Use sprintf() or strcpy()/strcat() to copy the strings into the allocated buffer.

Return a pointer to the resultant string.

To get you started, the top of your "concatenation" function should look like this:

char *
concatStrings(const char *s1,const char *s2)
{
char *result;
size_t len=strlen(s1)+strlen(s2);

result=malloc(len+1);

if (result!=NULL) {
/* Copy the strings to result */

If you need further help, post your best attempt.


Russ
bobbitts@hotmail.com

http://home.earthlink.net/~bobbitts

 

[SwapSawe]

char *chrptr;
printf("Enter the first String"
gets(string1);
printf("Enter the second String"
gets(string2);

chrptr = (char *) malloc(sizeof(strlen(string1)+strlen(string2)));


if(chrptr!=NULL)
// perform concatenation.
....
SwapSawe.

 

[rbobbitt]

But don't use gets(), it's a bug. Use fgets() instead.

Russ
bobbitts@hotmail.com

http://home.earthlink.net/~bobbitts