JavaScript: Reverse the bits of a given 16 bits unsigned short integer

Last update on May 30 2022 10:01:45 (UTC/GMT +8 hours)

JavaScript Basic: Exercise-138 with Solution

Write a JavaScript program to reverse the bits of a given 16 bits unsigned short integer.

Sample Solution:

HTML Code:

<!DOCTYPE html>
<html>
<head>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width">
  <title>Reverse the bits of a given 16 bits unsigned short integer</title>
</head>
<body>

</body>
</html>

JavaScript Code:

function sixteen_bits_reverse(num) {
	var result = 0;
	for (var i = 0; i < 16; i++) 
    {
		result = result * 2 + (num % 2);
		num = Math.floor(num / 2);
	}
	return result;
}
console.log(sixteen_bits_reverse(12345));
console.log(sixteen_bits_reverse(10));
console.log(sixteen_bits_reverse(5));

Sample Output:

39948
20480
40960

Flowchart:

ES6 Version:

function sixteen_bits_reverse(num) {
	let result = 0;
	for (let i = 0; i < 16; i++) 
    {
		result = result * 2 + (num % 2);
		num = Math.floor(num / 2);
	}
	return result;
}
console.log(sixteen_bits_reverse(12345));
console.log(sixteen_bits_reverse(10));
console.log(sixteen_bits_reverse(5));

Live Demo:

See the Pen javascript-basic-exercise-137 by w3resource (@w3resource) on CodePen.

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Next: Write a JavaScript program to check whether it is possible to rearrange characters of a given string in such way that it will become equal to another given string.

JavaScript: Tips of the Day

How to insert an item into an array at a specific index (JavaScript)?

What you want is the splice function on the native array object.

arr.splice(index, 0, item); will insert item into arr at the specified index (deleting 0 items first, that is, it's just an insert). In this example we will create an array and add an element to it into index 2:

var arr = []; arr[0] = "Jani"; arr[1] = "Hege"; arr[2] = "Stale"; arr[3] = "Kai Jim"; arr[4] = "Borge"; console.log(arr.join()); arr.splice(2, 0, "Lene"); console.log(arr.join());

Ref: https://bit.ly/2BXbp04