main.c

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

void s_reverse(char *str);
int isPalindropme(char *a);

void s_reverse(char *str)
{
	// Leeren und NULL string abfangen
	if (str == 0 || *str == 0)
		return;

	//Start an Anfang setzen
	char *start = str;
	// Ende auf Anfang + Laenge -1 (wegen \0 )
	char *end = start + strlen(str) - 1;
	char temp;

	while (end > start) {
		//tauschen
		temp = *start;
		*start = *end;
		*end = temp;

		++start;
		--end;
	}
}

int isPalindropme(char *a)
{
	char b[strlen(a)];

	strcpy(b, a);
	s_reverse(b);

	return strcmp(a, b) ==0;
}

int main(int argc, char *argv[])
{
	if (argc != 2) {
		printf("Error, no argument supplied");
		return 1;
	}

	char *n = argv[1];

	printf("Reverse: \n");
	s_reverse(n);
	printf("%s\n", n);

	printf("Palindrom? (0 = nein, 1 = ja): \n");
	s_reverse(n);
	printf("%d\n", isPalindropme(n));
	return 0;
}