/* K&R Ex 4-12. Adapt the idea of printd to write a recursive version of itoa;
 * that is, convert an integer into a string by calling a recursive routine. */

#include <stdio.h>

int itoa_recursive(int, char[]);

int main() {

    char s[1000];
    int n1 = -345;
    int n2 = 35532;

    itoa_recursive(n1, s);
    printf("%s\n", s);
    itoa_recursive(n2, s);
    printf("%s\n", s);

    return 0;
}

int itoa_recursive(int n, char s[]) {

    int i;

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