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Programming-Idioms

History of Idiom 41 > diff from v49 to v50

Edit summary for version 50 by daniel:
New C implementation by user [daniel]
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Version 49

2019-09-26, 15:47:48

Version 50

2019-09-26, 17:29:39

Idiom #41 Reverse a string

Create string t containing the same characters as string s, in reverse order.
Original string s must remain unaltered. Each character must be handled correctly regardless its number of bytes in memory.

Illustration

Idiom #41 Reverse a string

Create string t containing the same characters as string s, in reverse order.
Original string s must remain unaltered. Each character must be handled correctly regardless its number of bytes in memory.

Illustration
Imports 
#include <stdlib.h>
#include <string.h>
Code 
char *strrev(char *s)
{
	size_t len = strlen(s);
	char *rev = malloc(len + 1);

	if (rev) {
		char *p_s = s + len - 1;
		char *p_r = rev;

		for (; len > 0; len--)
			*p_r++ = *p_s--;
		*p_r = '\0';
	}
	return rev;
}
Comments bubble
Returns NULL on failure