Some opnion and idead about my roman number conver upto 4000 ..i love solving my way

JavaScript
1 
let myobjtest={1:"I",5:"V",10:"X",50:"L",100:"C",500:"D",1000:"M" };
//check romanthousand and fix;
function convertToRoman(gvnnum) {



  if(gvnnum<=10){return romanupten(gvnnum);}
  if (gvnnum<=50){return romantenuptofifity(gvnnum);}
  if (gvnnum<=100){return romanuphundred(gvnnum)}
  if(gvnnum<=500){return romanfivehundred(gvnnum);}
  if(gvnnum<=1000){return romanthousand(gvnnum);}
  if(gvnnum<=3999){return romanuptofourthousand(gvnnum);}
 }
 



function romanupten(num)
 {
 return num<=3?concatroman(myobjtest[1],num):num<=4?myobjtest[1]+myobjtest[5].toString():num===5?myobjtest[5]:num<=8?myobjtest[5]+concatroman(myobjtest[1],num-5):num===9?myobjtest[1]+myobjtest[10]:num===10?myobjtest[10]:undefined
 }
 
 function romantenuptofifity(num){
 return num<=19?myobjtest[10]+romanupten(num-10):num<=39?concatroman(myobjtest[10],parseInt(num.toString()[0]))+romanupten(parseInt(num.toString()[1])):num<=49?myobjtest[10]+myobjtest[50]+romanupten(parseInt(num.toString()[1])):num===50?myobjtest[50]:undefined
 }
 function romanuphundred(num){
   return num<=89?myobjtest[50]+concatroman(myobjtest[10],parseInt(num.toString()[0]-5))+romanupten(parseInt(num.toString()[1])):num<=99?myobjtest[10]+myobjtest[100]+romanupten(parseInt(num.toString()[1])):num===100?myobjtest[100]:undefined
 }
 function romanfivehundred(num){
 return num<=399?concatroman(myobjtest[100],parseInt(num.toString()[0]))+findd(parseInt(num.toString()[1]+num.toString()[2])):num<500?myobjtest[100]+myobjtest[500]+findd(parseInt(num.toString()[1]+num.toString()[2])):num===500?myobjtest[500]:undefined;
 }
 function romanthousand(num){
   return num<=599?myobjtest[500]+findd(parseInt(num.toString()[1]+num.toString()[2])):num<=899?myobjtest[500]+concatroman(myobjtest[100],parseInt(num.toString()[0]-5))+findd(parseInt(num.toString()[1]+num.toString()[2])):num<=999?myobjtest[100]+myobjtest[1000]+findd(parseInt(num.toString()[1]+num.toString()[2])):num===1000?myobjtest[1000]:undefined

 }
 function romanuptofourthousand(num){
   return num<=3999?concatroman(myobjtest[1000],parseInt(num.toString()[0]))+findd(parseInt(num.toString()[1]+num.toString()[2]+num.toString()[3])):undefined
 }

function findd(num){
  
  if(num<=10){return romanupten(num)};
  //if(num>50){ return romanuphundred(num)};
  if(num<=50) {
  return romantenuptofifity(num);}
  
  if(num<=100){return romanuphundred(num)};
  if(num<=500){return romanfivehundred(num)}
  if(num<=1000){return romanthousand(num)}
}
function concatroman(num,time){
    let hold="";
     while(time>0){
        hold=hold+num;
        time--;
    }
    return hold
}






convertToRoman(36);