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/**********************************************
The function printbin(int n) prints out the
binary representation of n, assuming n >= 0.
Notice that the base case is not explicit
here!
 **********************************************/
#include <stdio.h>

void printbin(int n);

int main() {
  // Get integer n, n >= 0
  int n;
  printf("Enter non-negative integer: ");
  fflush(stdout);
  scanf(" %i", &n);

  // Print the binary representation of n
  printf("In binary that's ");
  printbin(n);
  printf("\n");

  return 0;
}

void printbin(int n) {
  // Print everything but the last bit!
  if (n > 1) {
    printbin(n/2);
  }

  // Print out the last bit
  printf("%i", n%2);
}