JavaScript Fibonacci Calculator: How to output answer into text box? - javascript

I am currently trying to make a calculator that takes a numerical input (n) and shows the Fibonacci number to the nth sequence. I am a beginner at Javascript and just can't seem to make my code work:
HTML:
<head>
<script src="calculator.js"></script>
</head>
<body>
<input type="number" name="Input" value="" id="userInput" / >
<input type="button" value="Go" onclick="calculate();" />
<input type="number" name="Answer" id="userAnswer" />
</body>
JavaScript:
var input = document.getElementById("userInput");
var output = document.getElementById("userAnswer");
var answer;
function calculate(){
n = input.value;
if (n < 2){
return 1;
} else {
answer = calculate(n - 2) + calculate(n - 1);
return answer;
}
output.value = answer;
}

Don't be complex!
function calculate(n){
if (n < 2){
return 1;
} else {
return calculate(n - 2) + calculate(n - 1);
}
}
<head>
<script src="calculator.js"></script>
</head>
<body>
<input type="number" name="Input" value="" id="userInput" / >
<input type="button" value="Go" onclick="document.getElementById('userAnswer').value=calculate(document.getElementById('userInput').value);" /><br>
<input type="number" name="Answer" id="userAnswer" />
</body>

Related

HTML, how to get always +1 sum

I'm doing a point counter in general and I have no idea how to do it anymore, so I would like to add +1 to the sum on the "=" button and add it only once if someone could help me, I would be grateful
Code: https://pastebin.com/C26VFyev
var result = 0;
function suma() {
var cal1 = parseFloat(document.forms["form1"]["cal1"].value);
var cal2 = parseFloat(document.forms["form1"]["cal2"].value);
var sum = (cal1 + cal2 + 1);
document.forms["form1"]["sum"].value = sum
result = sum;
}
<html>
<head>
<script type="text/javascript" src="https://code.jquery.com/jquery-2.1.1.min.js"></script>
</head>
<body>
<form name="form1">
Cal 1:
<input value="0" name="cal1" size="5"><br> Cal2:
<input value="0" name="cal2" size="5"><br>
<input type="button" value="Oblicz" name="add" onClick="suma();"><br> Suma:
<input type="text" name="sum" size="6"><br>
<input type="reset" value="Reset"><br>
</form>
</body>
</html>
Use a variable for what you add to the sum. Initialize it to 1 for the first time, than change it to 0 for future uses.
var result = 0;
var addition = 1;
function suma() {
var cal1 = parseFloat(document.forms["form1"]["cal1"].value);
var cal2 = parseFloat(document.forms["form1"]["cal2"].value);
var sum = (cal1 + cal2 + addition);
if (addition == 1) {
addition = 0;
}
document.forms["form1"]["sum"].value = sum
result = sum;
}
<html>
<head>
<script type="text/javascript" src="https://code.jquery.com/jquery-2.1.1.min.js"></script>
</head>
<body>
<form name="form1">
Cal 1:
<input value="0" name="cal1" size="5"><br> Cal2:
<input value="0" name="cal2" size="5"><br>
<input type="button" value="Oblicz" name="add" onClick="suma();"><br> Suma:
<input type="text" name="sum" size="6"><br>
<input type="reset" value="Reset"><br>
</form>
</body>
</html>

how to auto sum multiple inputbox inner loop in javascript

I want to calculate my input box inner looping and this bellow is what if done please help me to solve this issue
<?php
$jumlah_form = 3;
for($i=1; $i<=$jumlah_form; $i++){
?>
<input type="text" id="txt1" onkeyup="sum1();" /></br>
<?php
}
?>
<input type="text" id="txt2" value= "0" /></br>
<script>
function sum1() {
var txtFirstNumberValue = document.getElementById('txt1').value;
var txtSecondNumberValue = document.getElementById('txt2').value;
var result = parseInt(txtFirstNumberValue) + parseInt(txtFirstNumberValue) ;
if (!isNaN(result)) {
document.getElementById('txt2').value = result;
}
}
</script>
Three input boxes are created by looping, I want to calculate three input box, and parse the result into result box whenever user input number
I think you are asking how to write the JavaScript so that it will add up the total of all the input boxes, no matter how many are created by the PHP?
If so then a good way would be to give all the textboxes the same class. Then, the JavaScript can just select all boxes with that class, loop through them and get the total value.
Here's a worked example using 3 textboxes (as if the PHP had generated them this way):
var textboxes = document.querySelectorAll(".sum");
textboxes.forEach(function(box) {
box.addEventListener("keyup", sumAll);
});
function sumAll() {
var total = 0;
textboxes.forEach(function(box) {
var val;
if (box.value == "") val = 0;
else val = parseInt(box.value);
total += val;
});
document.getElementById("total").innerText = total;
}
<input type="number" id="txt1" class="sum" value="0" /><br/>
<input type="number" id="txt2" class="sum" value="0" /><br/>
<input type="number" id="txt3" class="sum" value="0" /><br/>
<br/><br/> Total: <span id="total"></span>
To generate html with php:
$count = 5;
for($i=1;$i <= $count;$i++) {
echo "<input type='number' id='"."txt".i."' /></br>"
}
To calculate sum from inputs:
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Hello World</title>
</head>
<body>
<form onsubmit="submitForm(this); return false;" >
<input type="number" id='text1'>
<input type="number" id='text2'>
<input type="number" id='text3'>
<input type="number" id='text4'>
<input type="number" id='text5'>
<button type="submit" >Calculate</button>
</form>
<div>
<p>Result:</p>
<p id='result'></p>
</div>
<script>
function submitForm(form) {
let toReturn = 0;
const inputs = form.getElementsByTagName("input");
for(let x = 0; x < inputs.length; x++ ) {
toReturn += parseInt(inputs[x].value ? inputs[x].value : 0);
}
document.getElementById('result').innerHTML = toReturn;
return false;
}
</script>
</body>
</html>

how can i get input text value and pass in button onclick method in javascript function pass by values

function addData (n1, n2) {
alert(fn+ln);
}
<body>
<input Type="text" name="n1">
<input Type="text" name="n2">
<button onClick="addData(n1.value,n2.value)">click</button>
</body>
its give me the following error:
ReferenceError: n1 is not defined.
You cannot get the value of the input by using n1.value You need to obtain the DOM element using document.getElementById and use its value to obtain the string value and parse it as Integer before you add them.
See this:
function addData (n1, n2) {
n1Val = parseInt(n1.value);
n2Val = parseInt(n2.value);
alert(n1Val+n2Val);
}
<body>
<input Type="text" id="n1">
<input Type="text" id="n2">
<button onClick="addData(document.getElementById('n1'), document.getElementById('n2'))">click</button>
</body>
If you want to merely concatenate the data and not add it, just remove the parseInt call and add the strings like in the following example:
function addData (n1, n2) {
n1Val = n1.value;
n2Val = n2.value;
alert(n1Val+n2Val);
}
<body>
<input Type="text" id="n1">
<input Type="text" id="n2">
<button onClick="addData(document.getElementById('n1'), document.getElementById('n2'))">click</button>
</body>
Hope it helps!!
Do like this way:
function addData (e) {
var rec = 0;
var t = document.getElementsByTagName('input');
for(var i=0;i<t.length;i++){
rec=rec+parseInt(t[i].value);
}
console.log(rec);
}
<script>
</script>
<body>
<input Type="text" name="n1">
<input Type="text" name="n2">
<button onClick="addData(this)">click</button>
</body>
<html>
<head>
<title>Input tutorial</title>
<script language="javascript">
function addNumbers()
{
var val1 = parseInt(document.getElementById("value1").value);
var val2 = parseInt(document.getElementById("value2").value);
var ansD = document.getElementById("answer");
var final = val1 + val2;
alert(final);
}
</script>
</head>
<body>
value1 = <input type="text" id="value1" name="value1" value="1" /> value2 = <input type="text" id="value2" name="value2" value="2" />
<input type="button" name="Sumbit" value="Click here" onclick="javascript:addNumbers()" />
</body>
</html>

comparing a user given input to a string in javascript

parts of my code. it was supposed to count 2 if all of your answers were correct.
i am just a begginer at this. the error is that when i open my browser and click the "check?" nothing happens.
<head>
<script language="javascript">
function checker()
{
var myscore = 0;
if(parseInt(document.quiz.num1.value) == 6)
{ myscore = (myscore + 1);}
else
{ myscore;}
if(document.quiz.num2.value == type of "dry" )
{ myscore = (myscore + 1);}
else
{ myscore;}
document.myform.thescore.value = myscore;
}
</script>
</head>
<body>
<form name="quiz">
How many feet are ther in 1 Fathom? <input type="text" id="num1">
<br>
What type of stones can never be found in the ocean? <input type="text" id="num2">
<br>
My Score: <input type="text" id="thescore"><br>
<input type="button" value="Check?" onClick="checker()">
</form>
</body>
here is your answer:
<html>
<head>
<script lang="Java-Script">
var msg;
var sc;
function validateTest()
{
sc=0;
msg=document.frm.num1.value;
if(msg==6)
sc=sc+1;
msg=document.frm.num2.value;
if(msg=='dry')
sc=sc+1;
document.frm.thescore.value=sc;
return;
}
</script>
</head>
<body>
<form name="frm">
How many feet are there in 1 Fathom? <input type="text" name="num1"><br>
What type of stones can never be found in the ocean? <input type="text" name="num2"><br>
My Score: <input type="text" name="thescore"><br>
<input type="button" value="Submit" onclick="validateTest()">
</form>
</body>
</html>
i have already tested this, it will work.

compute sum dynamically with javascript

I have two textboxes Num1 and Num2 and another textbox Sum having the value 10.
How can I do this wherein if the user will enter a number for Num1, it will add it to Sum and dynamically change the displayed number in the Sum textbox. If the user will enter a number in Num2 it will also add that number to the updated number shown in Sum textbox and dynamically change the value for Sum textbox also.
How to do this in Javascript?
Something like that:
<input type="text" id="Num1" value="1" onblur="recalculateSum();"/>
<span>+</span>
<input type="text" id="Num2" value="1" onblur="recalculateSum();"/>
<span>=</span>
<input type="text" id="Sum" value=""/>
<script>
function recalculateSum()
{
var num1 = parseInt(document.getElementById("Num1").value);
var num2 = parseInt(document.getElementById("Num2").value);
document.getElementById("Sum").value = num1 + num2;
}
</script>
Another version.
<!DOCTYPE html>
<html>
<head>
<title>Summer</title>
</head>
<body>
Num 1: <input type="text" id="num1" name="num1" value="4"/&gt<br />
Num 2: <input type="text" id="num2" name="num2" value="6"/&gt<br />
Sum <input type="text" id="sum" name="sum" value="10">
<script type="text/javascript">
var _num1 = document.getElementById('num1');
var _num2 = document.getElementById('num2');
var _sum = document.getElementById('sum');
_num1.onblur = function(){
_sum.value = (parseInt(_sum.value,10) + parseInt(this.value,10));
};
_num2.onblur = function(){
_sum.value = (parseInt(_sum.value,10) + parseInt(this.value,10));
};
</script>
</body>
</html>
<input type="text" id="Num1" name="Num1"/>
<input type="text" id="Num2" name="Num2"/>
<input type="text" id="Sum" name="Sum"/>
function addNums() {
var num1 = parseInt(document.getElementById('Num1').value,10);
var num2 = parseInt(document.getElementById('Num2').value,10)
document.getElementById('Sum').value = (num1 + num2).toString();
}
There are other ways to reference the form items, but this one works.
<input type="text" id="Num1" value="1" onblur="recalculateSum();"/>
<input type="text" id="Num2" value="1" onblur="recalculateSum();"/>
<input type="text" id="Sum" value=""/>
<script>
function recalculateSum()
{
var num1 = parseInt(document.getElementById("Num1").value);
var num2 = parseInt(document.getElementById("Num2").value);
document.getElementById("Sum").value = num1 + num2;
}
</script>
<!DOCTYPE html>
<html>
<head>
<script type="text/javascript">
function calculate(){
var x=parseInt(document.getElementById("first").value);
var y=parseInt(document.getElementById("second").value);
document.getElementById("answer").value=(x+y);
}
</script>
<title>exam</title>
</head>
<body>
<form>
First:<input id="first" name="first" type="text"><br>
Second:<input id="second" name="second" type="text"><br>
Answer:<input id="answer" name="answer" type="text"><br>
<input onclick="calculate()" type="button" value="Addition">
</form>
</body>
</html>

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