easy68k code

I have my logic down for a program that needs to convert decimal to roman, (maximum number 3999) that needs to return a roman number.

here is my logic in c:

{
if(x>3999)
cout<<"error"<<endl;


while(x>=1000){cout<<"M";x-=1000;}

if(x>=900){cout<<"CM";x-=900;}
else if(x>=500){cout<<"D";x-=500;}
if(x>=400){cout<<"CD";x-=400;}

while(x>=100){cout<<"C";x-=100;}

if(x>=90){cout<<"XC";x-=90;}
else if(x>=50){cout<<"L";x-=50;}
if(x>=40){cout<<"XL";x-=40;}

while(x>=10){cout<<"X";x-=10;}

if(x>=9){cout<<"IX";x-=9;}
else if(x>=5){cout<<"V";x-=5;}
if(x==4){cout<<"IV";x-=4;}

while(x>0){cout<<"I";x-=1;}



return 0;
}

I was going to compare the strings to the values in each register, but I don't think that is the greatest idea.

DECIMAL DC.L '2989'
ENDSTR DC.B 00
ARRAY1 DC.B 3999, $F9F,1000,$4d, 500,$44, 100,$43, 50,$4c, 10,$58, 5,$56, 1,$49, 00,00
;"MMMCMXCIX","M","CM","D","CD","C","XC","L","XL","X","IX","V","IV","I"

Any suggestions? I do not want the code, I want ideas of how to do this. After I load my register and postincrement it to get to the last value, I compare it to 0 obviously to get to the end. How can I compare it to the roman number, and actually make it return a roman value?

While i am a fool in software,
i feel that a look up table defining roman numbers with decimal, hex or BCD definitions and later use the newly defined equivalents, should serve you.