printf Line Wrap

#include <stdio.h>
#include <stdlib.h>

void main()
{
int a = 0, b = 0, c;

printf ("Enter: ");
scanf ("%d", &b);

while (a < b){
  c = a % 10;
  a = a + 1;

  if (c == 0){
    printf ("\n");
  }

  printf ("*");

}


printf ("\n");
system ("pause");
}