xor.js

let calc = document.getElementById("calculate");

calc.onclick = function () {
  let input_type = document.getElementsByClassName("t")[0].value;
  let input_type2 = document.getElementsByClassName("t")[1].value;
  let output_type = document.getElementsByClassName("t")[2].value;
  var n1 = document.getElementById("first").value;
  var n2 = document.getElementById("second").value;
  if (input_type != input_type2) {
    document.getElementById("output").value = "Syntax Error";
    document.getElementById("output").style.backgroundColor = "red";
    document.getElementById("output").style.color = "white";
  } else {
    document.getElementById("output").style.backgroundColor = "white";
    document.getElementById("output").style.color = "black";
    if (input_type == 2) {
      n1 = parseInt(n1, 2);
      n2 = parseInt(n2, 2);
    } else if (input_type == 8) {
      n1 = parseInt(n1, 8);
      n2 = parseInt(n2, 8);
    } else if (input_type == 10) {
      n1 = parseInt(n1, 10);
      n2 = parseInt(n2, 10);
    } else if (input_type == 16) {
      n1 = parseInt(n1, 16);
      n2 = parseInt(n2, 16);
    }

    /************************************************************  Output *********************************************************/

    let ans = n1 ^ n2;
    let final_output;
    if (output_type == 2) {
      final_output = ans.toString(2);
    } else if (output_type == 8) {
      final_output = ans.toString(8);
    } else if (output_type == 10) {
      final_output = ans.toString(10);
    } else if (output_type == 16) {
      final_output = ans.toString(16);
    }

    document.getElementById("output").value = final_output;
  }
};