Convert Integer to String

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

void print_integer_as_string(int num) {
    if (num == 0)
    {
        printf("0");
        return; 
    }

    int is_neg = 0; // default 0 denotes not negative

    char buff[31];
    buff[30] = '\0';
    int i = 0;

    if (num < 0)
    {
        is_neg = 1; 
        num *= -1; 
    }

    while (num)
    {
        buff[i] = (num % 10) + '0';
        num /= 10;
        i++; 
    }

    if (is_neg)
    {
        buff[i] = '-';
        i++;
    }

    for (int j = i - 1; j >= 0; j--)
    {
        printf("%c", buff[j]);
        if (j >= 1) putchar(' ');
    }
}


int main() {
    int num;
    scanf("%d", &num);
    print_integer_as_string(num);
    return 0;
}