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#include <stdio.h>
#include <string.h>
#define MAXLEN 15
void reverse(char str[], size_t left, size_t right);
char* itoa(int n, char str[]);
void swap(char array[], int i, int j);
int
main(void)
{
int n = 42069;
char str[MAXLEN];
printf("%d\n", n);
printf("%s\n", itoa(n, str));
return 0;
}
void
reverse(char str[], size_t left, size_t right)
{
if (left >= right)
return;
swap(str, left, right);
reverse(str, left+1, right-1);
}
char*
itoa(int n, char str[])
{
int sign, i;
/* to include the most -ve int */
n = ((sign = n) < 0) ? -(n+1) : n-1;
i = 0;
do {
str[i++] = n%10 + '0';
} while ((n /= 10) > 0);
if (sign <0)
str[i++] = '-';
/* part of "to include the most -ve int" */
str[0] += 1;
str[i] = '\0';
reverse(str, 0, strlen(str)-1);
return str;
}
void
swap(char array[], int i, int j)
{
int temp;
temp = array[i];
array[i] = array[j];
array[j] = temp;
}
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