Get a string and store each character's ascii value in the array

Get a string from the user, and store the ascii value of each of the character of the string in a seperate integer array.

For example:

If the input string is 

the resultant ascii array is 
115 97 116 104 105 115 104


#include <stdio.h>
#include <stdlib.h>
int main(void) {
 /* Character pointer to point to starting character of the string */
 char *s;
 int i,*a,j;
 /* Dynamically allocate the memory for string / character array */
 /* Dynamically allocate memory for integer array */
 /* Get the input string from the user */
 /* Until we reach the end of the string, which is a null character '\0' of macro constant 0 */
  /* store each character's ascii value in the array a */
 /* Print the array which has the ascii values of characters of the string */
  printf("%d ",*(a+j));
 return 0;