tcpl-ex-4-12.c

tcpl-ex-4-12.c

/*
 * Exercise 4-12. Adapt the ideas of printd to write a recursive version of 
 * itoa; that is, convert an integer into a string by calling a recursive 
 * routine.  
 */
#include <math.h>
#include <string.h>


void itoa(int n, char s[])
{
	static int i;

	if (n / 10)
		itoa(n / 10, s);
	else 
	{
		i = 0;
		if (n < 0)
			s[i++] = '-';
	}
	s[i++] = abs(n) % 10 + '0';
	s[i] = '\0';
}

int main(void)
{
	int n = 100;
	char s[10];
	char exp[] = "100";
	itoa(n, s);
	if (strcmp(s, exp) == 0)
		printf("assert success.\n");
	else
		printf("assert fail.\n");

	return 0;
}