#include <stdio.h>
static int i, k;
void reverse(char s[]);
int main(void)
{
char s[]="hello world";
i= k= 0;
reverse(s);
return 1;
}
void reverse(char s[])
{
int c;
if ((c = s[i]) != '\0')
{
i++;
reverse(s);
}
if (c != '\0')
s[k++] = c;
}
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