“Syntax errors” appearing even though none seem to be present - javascript

I am writing a code that produces a random math quiz. However, when I run it (in an app called SoloLearn) it I get a Syntax error even though there doesn’t appear to be any. I even tested it in JSHint and no Syntax errors seemed to be present. Here is my code:
function random(max) {
return Math.floor(Math.random() * Math.floor(max));
}
function start() {
var form = document.getElementById("name_form");
var name = form.elements[0].value;
var score = 0;
alert("Let's begin!");
for (let i = 0; i < 4; i++) {
var num1 = random(10);
var num2 = random(10);
var operator = random(2);
if (operator == 0) {
var question = prompt(num1 + " + " + num2 + " =");
var answer = num1 + num2;
}
else {
var question = prompt(num1 + " - " + num2 = " =");
var answer = num1 - num2;
}
if (question == answer) {
alert("Correct!");
score++;
}
else {
alert("Incorrect ):");
}
}
document.write(score);
}
What is going on here?

In your line var question = prompt(num1 + " - " + num2 = " ="); you have misspelled a '+' which is a '=' in your code.
It should be:
var question = prompt(num1 + " - " + num2 + " =");
The same as #Nick Parsons said in the comments

Syntax error should be fixed by changing
var question = prompt(num1 + " - " + num2 = " =");
to
var question = prompt(num1 + " - " + num2 + " =");
which is the intent I believe

Related

Trying to make loop exit , but it currently just continues looping for 100 times

I am trying to make so when the looping of 100 hits on the character exits the loop when the life dice rolls to 0. How it currently is is all gets looped 100 times. I am not quite sure how I need to go about solving this, any tips would be helpful. My code is below.
function addChar(fname, lname, speed, agility, wep, outfit, mood) {
this.fname = fname;
this.lname = lname;
this.speed = speed;
this.agility = agility;
this.wep = wep;
this.outfit = outfit;
this.mood = mood;
this.special = function(specialMove) {
specialMove();
}
this.jumpKick = function() {
var jmpkckTimes = Math.floor(Math.random() * (100 - 33 + 1)) + 33;
document.write("He jumpkicks " + jmpkckTimes + " times. ");
if (jmpkckTimes > 70) {
document.write("He enters rage mode! ");
} else {
document.write("He does not have enough kicks for rage mode. ");
}
}
this.hits = function() {
var allHits = Math.floor(Math.random() * (100 - 33 + 1)) + 33;
document.write(" He gets attacked for " + allHits + " HP.");
}
this.lifes = function() {
var life = Math.floor(Math.random() * (3 - 0 + 1)) + 0;
if (life > 0) {
document.write(" The life dice rolls a " + life + ". You have survived! For now...");
} else {
document.write(" The life dice rolls a " + life + ". You have died!");
}
}
}
var myChar = new addChar('Johhny', 'Kicker', 10, 7, 'Ancient Greataxe', 'Barrows', 'angry');
document.write(myChar.fname + " " + myChar.lname + "'s speed is " + myChar.speed + "<br>");
document.write(myChar.fname + " " + myChar.lname + "'s agility is " + myChar.agility + "<br>");
document.write(myChar.fname + " " + myChar.lname + "'s weapon of choice is: " + myChar.wep + "<br>");
document.write(myChar.fname + " " + myChar.lname + " feels " + myChar.mood + "<br>");
document.write(myChar.fname + " " + myChar.lname + " attempts his special: ");
myChar.special(myChar.jumpKick)
for (i = 1; i < 101; i++) {
myChar.hits(myChar.allHits)
myChar.lifes(myChar.lifes)
}
function myOutfit() {
document.getElementById("demo").innerHTML = ("He is wearing " + myChar.outfit)
}
var start = Date.now();
var response = prompt("Do you think my character has what it takes?", "");
var end = Date.now();
var elapsed = (end - start) / 1000;
console.log("You took " + elapsed + " seconds" + " to type: " + response);
You need to have a way to communicate outside of the object, of what is happening inside the object.
For example, when something happens in a function, like lifes() or hits(), you should assign a value to a variable on the object to retain state. That way you can access the state from the for loop.
Example:
this.isAlive = true; // starting condition
this.lifes = function() {
var life = Math.floor(Math.random() * (3 - 0 + 1)) + 0;
this.isAlive = (life > 0);
if (this.alive) {
document.write('you survived');
} else {
document.write('you died');
}
Now in your for loop, you can access isAlive:
// loop until 100 attempts or you die, which ever comes first
for (i = 1; i < 101 && myChar.isAlive; i++) {
myChar.hits(myChar.allHits)
myChar.lifes(myChar.lifes)
}
well in general you can break out of foor loops aswell as prevent further execution of a foor loop and continue the next iteration:
for (var i = 0; i < 10; i++) {
if (i == 4) continue;
if (i == 8) break;
console.log(i);
}
this will basically print: 0, 1, 2, 3, 5, 6, 7
(as you can see it kind of skipped 4)
(it will also work in while / do while loops)
so in your case you could check if the return value of one of your functions is true or false or do some other kind of conditional checking in order to break out of the loop.
or similar to how Rob Brander wrote in his answer:
var maxTurns = 100;
var turns = 0;
while (myChar.isAlive && ++turns <= maxTurns) {
myChar.hits();
myChar.lifes();
}
console.log("character is: " + myChar.isAlive ? "alive" : "dead");
console.log("after: " + turns + " turns.");

Why isn't my code working? (TeamTreeHouse)

My code isn't working from a challenge in teamtree house
var input1 = prompt("Choose an integer");
var bottomNumber = parseInt(input1);
var input = prompt("choose a second integer");
var topNumber = parseInt(input);
var randomNumber = Math.floor(Math.random() * (topNumber - bottomNumber + 1)) + bottomNumber;
var message = "<p>" + randomNumber + " is a number between " + bottomNumber "and " + topNumber + ".</p>";
document.write(message);
I tried to Create a program that has 2 prompts both asking for integers then the it creates a random number betweeen the 2 numbers but on the website the prompts do not appear at all and the javaScript Console has the error:
Uncaught SyntaxError: Unexpected string
Thanks for all the help.
This should work:
var input1 = prompt("Choose an integer");
var bottomNumber = parseInt(input1);
var input = prompt("choose a second integer");
var topNumber = parseInt(input);
var randomNumber = Math.floor(Math.random() * (topNumber - bottomNumber + 1)) + bottomNumber;
var message = "<p>" + randomNumber + " is a number between " + bottomNumber + "and " + topNumber + ".</p>";
document.write(message);
Try to interpret the error that appears in the console for a better idea.
The issue was missing a '+' and opening up the browser console will pretty much indicate that.
You are missing a + in your string building.
var message = "<p>" + randomNumber + " is a number between " + bottomNumber + "and " + topNumber + ".</p>";
Fiddle: http://jsfiddle.net/wLpyzwLL/

No prompt from JS

This code only gets me to link address but doesn't run the function. (the last alert() function doesn't run).
I need this alert, what I am doing wrong?
Here is my code:
<html>
<head>
<title>Laboratorul nr_3</title>
<meta charset="utf-8"/>
<script language="javascript"><!--
function ex1()
{
num = prompt("Input the number");
result = num * 3;
alert(num + " x " + 3 + " = " + result);
num2 = prompt("Input number to add");
result2 = num * 3 + parseint(num2);
alert(num + " x " + 3 + " + " num2 " = " + result2);
}
//--></script>
</head>
<body>
link
</body>
</html>
You have to cancel the native action (following the link):
function ex1() {
// code...
return false;
}
Or use a different element that doesn't do anything, maybe a <button> or <div>.
There was only 3 errors you didn't call the function and you didn't concate the string and the parseInt, int cannot be spelled in lower case
function ex1(){
num = prompt("Input the number");
result = num * 3;
alert(num + " x " + 3 + " = " + result);
num2 = prompt("Input number to add");
result2 = num * 3 + parseInt(num2);
alert(num + " x " + 3 + " + " + num2 +" = " + result2);
}
ex1()

math array homework issue coding javascript?

this is what i have but i need to record the problems that are wrong and have the user answer them until there right, keep prompting the user for the problem until its right this was a 4 part problem and part3 is to have the same problem repeat until its completed
ex.(7+1=6) repeat(7+1=4) repeat (7+1=8) next problem
the user has to complete 5 problems and they have to be correct
<html>
<script>
var file=0;
var fileIndex=new Array();
var user=prompt("what is "+a+" + "+b);
var arr=[user,user,user,user,user];
var a=Math.floor(Math.random()*11);
var b=Math.floor(Math.random()*11);
var answer=parseInt(a+b);
var user=prompt("what is "+a+" + "+b);
while (user != answer && file++ != 4) {
fileIndex.push(user);
user = prompt("what is " + a + "+" + b);
} else {
alert("answer is:" + answer);
}
}//close for
</script>
Update:
var a = 1,
b = 1;
var answer = a + b,
tick = 0;
var file_index = [], copy;
function randomize() {
a = Math.floor(Math.random() * 11);
b = Math.floor(Math.random() * 11);
answer = a + b;
}
while (1)
{
if ((copy = prompt("What is " + a + " + " + " b?", 0)) != answer)
{
if (!copy) break;
file_index.push(copy);
randomize();
} else if (tick == 4) {
break;
} else {
++tick;
}
}
jsFiddle Demo

Javascript function - works in IE, not in chrome

To preface this, we are a small organization and this system was built by someone long ago. I am a total novice at javascript so I have trouble doing complicated things, but I will do my best to understand your answers. But unfortunately redoing everything from scratch is not really an option at this point.
We have a system of collecting data where clients use a login to verify a member ID, which the system then uses to pull records from an MS Access database to .ASP/html forms so clients can update their data. One of these pages has the following function that runs on form submit to check that data in fields a/b/c sum to the same total as d/e/f/g/h/i. It does this separately for each column displayed (each column is a record in the database, each a/b/c/d/e/f is a field in the record.)
The problem is with this section of the function:
for (var j=0; j<recCnt; j++) {
sumByType = milesSurf[j] + milesElev[j] + milesUnder[j];
sumByTrack = milesSingle[j] + milesDouble[j] + milesTriple[j] + milesQuad[j] + milesPent[j] + milesSex[j];
etc.
It should use javascript FOR to loop through each record and test to see if they sum to the same thing.
In Firefox and IE this is working properly; the fields sum properly into "sumByType" and "sumByTrack". You can see below I added a little alert to figure out what was going wrong:
alert(sumByType + " " + j + " " + recCnt + " " + milesSurf[j] + " " + milesElev[j] + " " + milesUnder[j]);
In Chrome, that alert tells me that the components of "sumByType" and "sumByTrack" (the various "milesXXXXX" variables) are undefined.
My question is: Why in Chrome is this not working properly, when in IE and FFox it is? Any ideas?
Full function code below:
function submitCheck(formy, recCnt) {
//2/10/03: added milesQuad
//---------------checks Q#4 that Line Mileage by type is the same as by track
var milesElev = new Array();
var milesSurf = new Array();
var milesUnder = new Array();
var milesSingle = new Array();
var milesDouble = new Array();
var milesTriple = new Array();
var milesQuad = new Array();
var milesPent = new Array();
var milesSex = new Array();
var sumByType = 0;
var milesLineTrack = new Array(); //this is for Q5 to compare it to mileage by trackage
var j = 0; var sumByTrack = 0; var liney; var yrOp;
//var str = "document.frm.milesElev" + j;
//alert(str.value);
for (var i in document.frm) {
if (i.substring(0, i.length - 1) == "milesElev") {
milesElev[parseInt(i.substring(i.length-1, i.length))] = parseFloat(document.frm[i].value); }
if (i.substring(0, i.length - 1) == "milesSurf") {
milesSurf[parseInt(i.substring(i.length-1, i.length))] = parseFloat(document.frm[i].value); }
if (i.substring(0, i.length - 1) == "milesUnder") {
milesUnder[parseInt(i.substring(i.length-1, i.length))] = parseFloat(document.frm[i].value); }
if (i.substring(0, i.length - 1) == "milesSingle") {
milesSingle[parseInt(i.substring(i.length-1, i.length))] = parseFloat(document.frm[i].value); }
if (i.substring(0, i.length - 1) == "milesDouble") {
milesDouble[parseInt(i.substring(i.length-1, i.length))] = parseFloat(document.frm[i].value); }
if (i.substring(0, i.length - 1) == "milesTriple") {
milesTriple[parseInt(i.substring(i.length-1, i.length))] = parseFloat(document.frm[i].value); }
if (i.substring(0, i.length - 1) == "milesQuad") {
milesQuad[parseInt(i.substring(i.length-1, i.length))] = parseFloat(document.frm[i].value); }
if (i.substring(0, i.length - 1) == "milesPent") {
milesPent[parseInt(i.substring(i.length-1, i.length))] = parseFloat(document.frm[i].value); }
if (i.substring(0, i.length - 1) == "milesSex") {
milesSex[parseInt(i.substring(i.length-1, i.length))] = parseFloat(document.frm[i].value); }
if (i.substring(0, i.length -1) == "milesLineTrack") {
milesLineTrack[parseInt(i.substring(i.length-1, i.length))] = document.frm[i].value; } //12/13/02 used to be parseFloat(document.frm[i].value)
if (i.substring(0,5)=="Lines") {
liney = document.frm[i].value;
if (parseInt(liney)<1 || isNaN(liney)) {
alert("Each mode must have at least 1 line. Please correct the value in question #2.");
document.frm[i].select(); return false; }}
if (i.substring(0,8)=="yearOpen") {
yrOp = document.frm[i].value;
if (parseInt(yrOp)<1825 || isNaN(yrOp)) {
alert("Please enter a year after 1825 for question #3");
document.frm[i].select(); return false; }
}
}
for (var j=0; j<recCnt; j++) {
sumByType = milesSurf[j] + milesElev[j] + milesUnder[j];
sumByTrack = milesSingle[j] + milesDouble[j] + milesTriple[j] + milesQuad[j] + milesPent[j] + milesSex[j];
//---------------to round sumByTrack and sumByType from a long decimal to a single decimal place, like frm 7.89999998 to 7.9.
sumByTrack = sumByTrack * 10;
if (sumByTrack != parseInt(sumByTrack)) {
if (sumByTrack - parseInt(sumByTrack) >= .5) {
//round up
sumByTrack = parseInt(sumByTrack) + 1; }
else { //truncate
sumByTrack = parseInt(sumByTrack); }}
sumByTrack = sumByTrack / 10;
sumByType = sumByType * 10;
if (sumByType != parseInt(sumByType)) {
if (sumByType - parseInt(sumByType) >= .5) {
//round up
sumByType = parseInt(sumByType) + 1; }
else { //truncate
sumByType = parseInt(sumByType); }}
sumByType = sumByType / 10;
//-------------end of rounding ---------------------------
if (sumByType != sumByTrack) {
if (isNaN(sumByType)) {
sumByType = "(sum of 4.a., b., and c.) "; }
else {
sumByType = "of " + sumByType; }
if (isNaN(sumByTrack)) {
sumByTrack = "(sum of 4.d., e., f., g., h., and i.) "; }
else {
sumByTrack = "of " + sumByTrack; }
alert("For #4, the 'End-to-End Mileage By Type' " + sumByType + " must equal the 'End-to-end Mileage By Trackage' " + sumByTrack + ".");
alert(sumByType + " " + j + " " + recCnt + " " + milesSurf[j] + " " + milesElev[j] + " " + milesUnder[j]);
return false;
}
//alert (milesLineTrack[j] + " " + milesSingle[j] + " " + 2*milesDouble[j] + " " + 3*milesTriple[j] + " " + 4*milesQuad[j] + " " + 5*milesPent[j] + " " + 6*milesSex[j]);
var singDoubTrip = (milesSingle[j] + 2*milesDouble[j] + 3*milesTriple[j] + 4*milesQuad[j] + 5*milesPent[j] + 6*milesSex[j])
//----------round singDoubTrip to one digit after the decimal point (like from 6.000000001 to 6.0)
singDoubTrip = singDoubTrip * 10;
if (singDoubTrip != parseInt(singDoubTrip)) {
if (singDoubTrip - parseInt(singDoubTrip) >= .5) {
//round up
singDoubTrip = parseInt(singDoubTrip) + 1; }
else { //truncate
singDoubTrip = parseInt(singDoubTrip); }}
singDoubTrip = singDoubTrip / 10;
//----------end round singDoubTrip-----------------------------------------
if (parseFloat(milesLineTrack[j]) != singDoubTrip) {
//var mlt = milesLineTrack[j];
//if isNaN(milesLineTrack[j]) { mlt =
alert("For column #" + (j+1) + ", the mainline passenger track mileage of " + milesLineTrack[j] + " must equal the single track plus 2 times the double track plus 3 times the triple track plus 4 times the quadruple track plus 5 times the quintuple track plus 6 times the sextuple track, which is " + singDoubTrip + ".");
return false;
}
}
//---------------------end of checking Q#4----------------
//return false;
}
I think for (var i in document.frm) is the problem. You should not enumerate a form element, there will be plenty of unexpected properties - see Why is using "for...in" with array iteration a bad idea?, which is especially true for array-like objects. I can't believe this works properly in FF :-)
Use this:
var ele = document.frm.elements; // or even better document.getElementById("frm")
for (var i=0; i<ele.length; i++) {
// use ele[i] to access the element,
// and ele[i].name instead of i where you need the name
}
Also, you should favour a loop over those gazillion of if-statements.

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