Htykuut

After looking at all the suggested threads, which didn't help, so I'm post ing this. I'm new to javascript and I've coded this algo to take a user input that is a string of 10 digits, convert it to an array and then perform a calculation to get a 13 digit ISBN number (I'm a library information technology student)

When I copy and past my code, not all of it shows up and it says I have code that's not formatted as code. This isn't for my homework, I'm going beyond the requirements by trying to do javascript so there's nothing unethical about asking for help I don't think.

I tried posting my code but it says it's not code so if you follow this link you can see a picture of my code.

Thanks for any insight, input comments or demands for clarification or anything.

https://i.postimg.cc/vmx7hB7Q/code.png

<input type="text" id="input" maxlength="10" size="7">  

            <button id="input" onclick="myfunction();">Click me</button>

            <script type="text/javascript" src="app.js">

                var input = "input";

                document.getElementById("input").value = input; 





                function assign(arr, vars) {

                var x = {};

                var num = math.min(arr.length, vars.length);

                for (var i = 0; i < num; ++i) {

                    x[vars[i]] = arr[i];

                    }

                    return x;

                    }

                    var arr =[1, 2, 3, 4, 5, 6, 7, 8, 9, 10];

                    var x = assign(arr, ['a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j',]);

                    var z = (9 + 21 + 8 + (var a*3) + var b + (var c*3) + var d + (var e*3) + var f + (var g*3) + var h + (var i*3) + var j);

                    var w = (var z % 10);

                    var v = ("978" + var a, var b, var c, var d, var e, var f, var g, var h, var i, var w);

                    document.getElementById('v').innerHTML = var v;



            </script>



            <div id="output"> </div>



    </div>