All the changes are down at the bottom

void say_number(const int n)
{ if (n==0) print("zero");
  else if (n==1) print("one");
  else if (n==2) print("two");
  else if (n==3) print("three");
  else if (n==4) print("four");
  else if (n==5) print("five");
  else if (n==6) print("six");
  else if (n==7) print("seven");
  else if (n==8) print("eight");
  else if (n==9) print("nine");
  else if (n==10) print("ten");
  else if (n==11) print("eleven");
  else if (n==12) print("twelve");
  else if (n==13) print("thirteen");
  else if (n==14) print("fourteen");
  else if (n==15) print("fifteen");
  else if (n==16) print("sixteen");
  else if (n==17) print("seventeen");
  else if (n==18) print("eighteen");
  else if (n==19) print("nineteen");
  else if (n==20) print("twenty");
  else if (n<0)
  { print("minus ");
    say_number(-n); }
  else if (n==30) print("thirty");
  else if (n==40) print("forty");
  else if (n==50) print("fifty");
  else if (n==60) print("sixty");
  else if (n==70) print("seventy");
  else if (n==80) print("eighty");
  else if (n==90) print("ninety");
  else if (n<100)
  { say_number(n/10*10);
    print("-");
    say_number(n%10); }
  else if (n<1000)
  { say_number(n/100);
    print(" hundred");
    if (n%100 != 0)
    { print(" and ");
      say_number(n%100); } }
  else if (n<1000000)
  { say_number(n/1000);
    print(" thousand");
    if (n%1000!=0)
    { print(" ");
      if (n%1000<100)
        print("and ");
      say_number(n%1000); } }
  else if (n<1000000000)
  { say_number(n/1000000);
    print(" million");
    if (n%1000000!=0)
    { print(" ");
      if (n%1000000<100)
        print("and ");
      say_number(n%1000000); } }
  else
    something(); }

Well, this just isn't interesting any more.

But we do need to look at the next stage.