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JavaScript - Position of the rightmost set bit of a number

JavaScript Bit Manipulation: Exercise-12 with Solution

Write a JavaScript program to find the position of the rightmost set bit of a given number. Set bits in a binary number is represented by 1.

Test Data:
(34) -> 2
Explanation:
34 in binary is 100010
Set bits in the 2nd position of the said binary format.
(104) -> 4
Explanation:
104 in binary is 1101000
Set bits in the 4th position of the said binary format.

Sample Solution:

JavaScript Code:

const turn_On_Kth_Bit = (n, k) => {
 if (typeof n!= "number") {
     return 'It must be number!'
     }
   if ((n & 1) != 0) {
            return 1;
        }
   n = n ^ (n & (n - 1));
   pos = 0;
   while (n != 0)
     {
       n = n >> 1;
       pos++;
      }
 
  return pos;
 }

n = 34
console.log(n + " in binary is " + n.toString(2))
position = turn_On_Kth_Bit(n);
console.log("Position of the rightmost set bit of the said number: " + position)
 
n = 104
console.log(n + " in binary is " + n.toString(2))
position = turn_On_Kth_Bit(n);
console.log("Position of the rightmost set bit of the said number: " + position)

Sample Output:

34 in binary is 100010
Position of the rightmost set bit of the said number: 2
104 in binary is 1101000
Position of the rightmost set bit of the said number: 4

Flowchart:

Flowchart: JavaScript - Position of the rightmost set bit of a number.

Live Demo:

See the Pen javascript-bit-manipulation-exercise-12 by w3resource (@w3resource) on CodePen.


* To run the code mouse over on Result panel and click on 'RERUN' button.*

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JavaScript: Tips of the Day

function and arguments

const person = {
  name: 'Lydia Hallie',
  hobbies: ['coding'],
};

function addHobby(hobby, hobbies = person.hobbies) {
  hobbies.push(hobby);
  return hobbies;
}

addHobby('running', []);
addHobby('dancing');
addHobby('baking', person.hobbies);

console.log(person.hobbies);

The addHobby function receives two arguments, hobby and hobbies with the default value of the hobbies array on the person object.
First, we invoke the addHobby function, and pass "running" as the value for hobby and an empty array as the value for hobbies. Since we pass an empty array as the value for y, "running" gets added to this empty array.
Then, we invoke the addHobby function, and pass "dancing" as the value for hobby. We didn't pass a value for hobbies, so it gets the default value, the hobbies property on the person object. We push the hobby dancing to the person.hobbies array.
Last, we invoke the addHobby function, and pass "bdaking" as the value for hobby, and the person.hobbies array as the value for hobbies. We push the hobby baking to the person.hobbies array.
After pushing dancing and baking, the value of person.hobbies is ["coding", "dancing", "baking"]

Ref: https://bit.ly/2Hcpkm6