NumberConvertor

function solve() {

   let sendButton = document.getElementById("send");
   let inputForm = document.getElementById("input");
   let selectMenuFrom = document.getElementById("selectMenuFrom");
   let selectMenuTo = document.getElementById("selectMenuTo");
   let resultOutputForm = document.getElementById("result");

   let optionElement = document.getElementsByTagName("option")[1];
   optionElement.value = "binary";
   optionElement.textContent = "Binary";

   let createOptionElement = document.createElement("option");
   createOptionElement.value = "hexadecimal";
   createOptionElement.textContent = "Hexadecimal";

   selectMenuTo.appendChild(createOptionElement);

   sendButton.addEventListener("click", function (){
      let inputFormValue = Number(inputForm.value);
      let valueOfForm = selectMenuTo.value;

      if (valueOfForm === "binary") {
         let numberToBinary = inputFormValue.toString(2);
         resultOutputForm.value = numberToBinary;
      } else if (valueOfForm === "hexadecimal"){
         let numberToHexadecimal = inputFormValue.toString(16);
         resultOutputForm.value = numberToHexadecimal.toUpperCase();
      }

   });

}