问如何从3位整数中提取1位数？

EN

#include<stdio.h>
int main()
{
  int di , i , num , pow = 1;
  setbuf ( stdout , NULL);
  printf ("enter the number of digits of the number\n");// specify at run time what will be the number of digits of the array.
  scanf ( "%d" , &di);
  int a[di];

  printf ("enter the %d digit number:\n",di);// 
  scanf ( "%d" , &num);//One thing is to be noted here that user can enter more digits than specified above , It is up to user to enter the specified digits , you can improve this program by making a check whether user enters the specified digits or not , better do it as exercise.
  while( di > 1 )
    {
    pow = pow * 10;
    di--;
    }

  i = 0;
  while ( num > 0)
    {
      a[i]=num/pow;
      num=num%pow;
      pow=pow/10;
      i++;
    }
  printf("the digits from the beginning are :\n"); 
  for(int j = 0 ; j < i ; j++)
    printf("%d\n",a[j]);
  return 0;
}