/*******************************************************************************
 * K&R 3-4
 *
 * So the issue here is that the range that can be represented using
 * signed ints always has just one more on the negative side. To avoid this
 * an unsigned int can be used to hold the negative value. It can be extracted
 * from the int by obtaining the two's compliment, applying a bitwise not and 
 * adding one. My gcc still flags this for some reason, as if -n and (~n +1) 
 * are the same. But the output is correct. 
 *
 *  int to string (itoa)
 *
 * program: itoa
 * by.....: yetimach
 * date...: 5 November 2024
 *
 * ****************************************************************************/



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

#define MAX 12 

char gs[MAX]; /* global string */

void reverse(char s[]){
    int c, i, j;

    for (i = 0, j = strlen(s)-1; i < j; i++, j--){
        c = s[i];
        s[i] = s[j];
        s[j] = c;
    }
}

void itoa(int n, char s[]){
    int i, sign;
    unsigned int un;

    if ((sign = n) < 0)
        un = ~n +1;
    else
        un = n;
    i = 0;
    do {
        s[i++] = un % 10 + '0';
    } while ((un /= 10) > 0);
    if (sign < 0)
        s[i++] = '-';
    s[i] = '\0';
    reverse(s);
}

int main(void)
{
    printf("Enter an integer value: ");
    int num;
    scanf("%d", &num);
    itoa(num, gs);
    printf("\nThe integer has been converted to a string: %s\n", gs);
    return 0;
}