What will be the equivalent output of the following JavaScript code snippet?
x = ~-y;
w = x = y = z;
q = a?b:c?d:e?f:g;
w = x = y = z;
q = a?b:c?d:e?f:g;
x = ~(-y); w = (x = (y = z));
q = a?b:(c?d:(e?f:g));
x = a?b:(c?d:(e?f:g));
q = ~(-y); w = (x = (y = z));
x = (x = (y = z));w = ~(-y);
q = a?b:(c?d:(e?f:g));
x = ~(-y); w = (x = (y = z));
q = (c?d:(e?f:g));
Correct Answer :
A.
x = ~(-y); w = (x = (y = z));
q = a?b:(c?d:(e?f:g));
Explanation: Brackets have higher precedence than any other operator. The placement of brackets results in the same result as without putting any bracket.
Related Questions
What will be the output of the following JavaScript code?
const obj1 =
{
property1: 21
}
const descriptor1 = Object.getOwnPropertyDescriptor(obj1, 'property1');
console.log(descriptor1.configurable);
console.log(descriptor1.enumerable);
{
property1: 21
}
const descriptor1 = Object.getOwnPropertyDescriptor(obj1, 'property1');
console.log(descriptor1.configurable);
console.log(descriptor1.enumerable);
true 21
true false
true true
false false
What will be the output of the following JavaScript code?
int a=4;
int b=1;
int c=0;
If(a==b)
document.write(a);
else if(a==c)
document.write(a);
else
document.write(c);
int b=1;
int c=0;
If(a==b)
document.write(a);
else if(a==c)
document.write(a);
else
document.write(c);
4
1
Error
0
What will be the firstname and surname of the following JavaScript code?
var book = {
main title: JavaScript,
'sub-title': The Definitive Guide,
for: all audiences,
author: {
firstname: David,
surname: Flanagan
}
};
main title: JavaScript,
'sub-title': The Definitive Guide,
for: all audiences,
author: {
firstname: David,
surname: Flanagan
}
};
properties
property values
property names
objects
JavaScript can be written __________
directly into JS file and included into HTML
directly on the server page
directly into HTML pages
directly into the css file
The expression of calling (or executing) a function or method in JavaScript is called ________
Primary expression
Functional expression
Invocation expression
Property Access Expression
Consider the following code snippet.
function printArray(a)
{
var len = a.length, i = 0;
if (len == 0)
console.log(Empty Array);
else
{
do
{
console.log(a[i]);
} while (++i < len);
}
}
What does the above code result?
{
var len = a.length, i = 0;
if (len == 0)
console.log(Empty Array);
else
{
do
{
console.log(a[i]);
} while (++i < len);
}
}
Prints the numbers in the array in order
Prints the numbers in the array in the reverse order
Prints 0 to the length of the array
Prints Empty Array
What will be the output of the following JavaScript code?
function height()
{
var height = 123.56;
var type = (height>=190) ? tall : short;
return type;
}
{
var height = 123.56;
var type = (height>=190) ? tall : short;
return type;
}
123.56
190
tall
short
The generalised syntax for a real number representation is __________
[digits][.digits][(E|e)[(+|-)]digits]
[digits][+digits][(E|e)[(+|-)]digits]
[digits][(E|e)[(+|-)]digits]
[.digits][digits][(E|e)[(+|-)]digits]
When does the function name become optional in JavaScript?
When the function is defined as a looping statement
When the function is defined as expressions
When the function is predefined
when the function is called
The script tag must be placed in __________
the head tag
the head or body
the title or head
after the body tag
Consider the following code snippet :
var tensquared = (function(x) {return x*x;}(10));
Will the above code work ?
Yes, perfectly
Error
Exception will be thrown
Memory leak
The pop() method of the array does which of the following task?
decrements the total length by 1
increments the total length by 1
prints the first element but no effect on the length
updates the element
What will be the output of the following JavaScript code?
var a=5 , b=1
var obj = { a : 10 }
with(obj)
{
alert(b)
}
var obj = { a : 10 }
with(obj)
{
alert(b)
}
10
Error
1
5
What is a block statement in JavaScript?
conditional block
block that contains a single statement
both conditional block and a single statement
block that combines multiple statements into a single compound statement
Consider the following code snippet.
for(var p in o)
console.log(o[p]);
The above code is equivalent to which code?
console.log(o[p]);
for (var i = 0;i < a.length;i++)
console.log(a[i]);
for (int i = 0;i < a.length;i++)
console.log(a[i]);
for (var i = 0;i <= a.length;i++)
console.log(a[i]);
for (var i = 1;i < a.length;i++)
console.log(a[i]);
Consider the following code snippet
function f(o)
{
if (o === undefined) debugger;
}
What could be the task of the statement debugger?
{
if (o === undefined) debugger;
}
It does nothing but a simple breakpoint
It debugs the error in that statement and restarts the statements execution
It is used as a keyword that debugs the entire program at once
It is used to find error in the statement
The var and function are __________
Keywords
Declaration statements
Data types
Prototypes
What will be the output of the following JavaScript code?
int sum=0;
var arr = [10,15,20,30];
arr.forEach(function myFunction(element)
{
sum= sum+element;
});
document.writeln(sum);
var arr = [10,15,20,30];
arr.forEach(function myFunction(element)
{
sum= sum+element;
});
document.writeln(sum);
70
75
10
error
Which of the operator is used to test if a particular property exists or not?
in
exist
within
exists
Consider the following code snippet :
var string2Num=parseInt(123xyz);
The result for the above code snippet would be :
123
123xyz
Exception
NaN
A function definition expression can be called as __________
Function prototype
Function literal
Function calling
Function declaration
What will be the output of the following Javascript code?
var txt1 = good;
var txt2 = day;
document.getElementById(demo).innerHTML = txt1 + txt2;
var txt2 = day;
document.getElementById(demo).innerHTML = txt1 + txt2;
good day
goodday
error
undefined
JavaScript Code can be called by using ___________
RMI
Triggering Event
Preprocessor
Function/Method
The type of a variable that is volatile is _______________
Volatile variable
Mutable variable
Immutable variable
Dynamic variable
A function with no return value is called ___________
Procedures
Method
Static function
Dynamic function
What will be the output of the following JavaScript code?
function compare()
{
int num=2;
char b=2;
if(a==b)
return true;
else
return false;
}
{
int num=2;
char b=2;
if(a==b)
return true;
else
return false;
}
true
false
runtime error
compilation error
What will be the output of the following Javascript code?
var add=new Function(num1,num2,return num1+num2);
document.writeln(add(2,5));
document.writeln(add(2,5));
2
5
Error
7
What will be the output of the following JavaScript code?
var a1 = [,,,];
var a2 = new Array(3);
0 in a1
0 in a2
var a2 = new Array(3);
0 in a1
0 in a2
true false
false true
true true
false true
Which of the following Attribute is used to include External JS code inside your HTML Document?
src
ext
script
link
What will be the output of the following JavaScript code?
var grade='B';
var result;
switch(grade)
{
case 'A':
{
result+=10;
break;
}
case 'B':
{
result+= 9;
break;
}
case 'C':
{
result+= 8;
break;
}
default:
result+= 0;
}
document.write(result);
var result;
switch(grade)
{
case 'A':
{
result+=10;
break;
}
case 'B':
{
result+= 9;
break;
}
case 'C':
{
result+= 8;
break;
}
default:
result+= 0;
}
document.write(result);
10
9
8
0