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Programming-Idioms

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Idiom #41 Reverse a string

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

Turning the string "café" into "éfac"
t = ''.join(reversed(s))
t = s[::-1]
#include <algorithm>
#include <string>
auto t = ::std::ranges::reverse(s);
for ($i=0;$i<mb_strlen($s);$i++) {
    $characters[] = mb_substr($s, $i, 1, 'UTF-8');
}

$characters = array_reverse($characters);
$t = implode($characters);

This solution needs mb (multibyte) extension.
#include <stdlib.h>
#include <string.h>
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;
}

Returns NULL on failure

New implementation...
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