JavaScript - Turn off the k^th bit of a given number

JavaScript Bit Manipulation: Exercise-9 with Solution

Turn Off kth Bit

Write a JavaScript program to turn off the k^th bit in a given number. Return the updated number.

Test Data:
(30, 3)-> 26

Explanation:
Binary format of 30 is -> 11110
Fortmat of the said number after off the 3rd bit -> 11010
After converting 11010 to decimal : 11010 -> 26
(100, 6) -> 68
Explanation:
Binary format of 100 is -> 1100100
Fortmat of the said number after off the 6th bit -> 1000100
After converting 1000100 to decimal : 1000100 -> 68

Sample Solution:

JavaScript Code:

// Define a function to turn off the kth bit of a number
const turn_Off_Kth_Bit = (n, k) => {
  // Check if the input is not a number
  if (typeof n != "number") {
    return 'It must be number!'; // Return an error message
  }
  // Return the result of performing a bitwise AND operation with the complement of the kth bit
  return n & ~(1 << (k - 1));
}

// Initialize variables n and k with values
let n = 30;
let k = 3;

// Display the binary representation of n
console.log(n + " in binary is " + n.toString(2));
console.log("Turning k'th bit off," + " k = " + k);

// Call the turn_Off_Kth_Bit function and display the result
let result_n = turn_Off_Kth_Bit(n, k);
console.log(result_n + " in binary is " + result_n.toString(2));

// Update variables n and k with new values
n = 100;
k = 6;

// Display the binary representation of n
console.log(n + " in binary is " + n.toString(2));
console.log("Turning k'th bit off," + " k = " + k);

// Call the turn_Off_Kth_Bit function and display the result
result_n = turn_Off_Kth_Bit(n, k);
console.log(result_n + " in binary is " + result_n.toString(2));

Output:

30 in binary is 11110
Turning k'th bit off, k = 3
26 in binary is 11010
100 in binary is 1100100
Turning k'th bit off, k = 6
68 in binary is 1000100

Flowchart:

Live Demo:

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

For more Practice: Solve these Related Problems:

• Write a JavaScript function that turns off (clears) the kth bit of a given integer using bitwise AND with a negated mask.
• Write a JavaScript function that validates the input and returns an error if k is not a valid bit position.
• Write a JavaScript function that displays the binary representation before and after turning off the kth bit.
• Write a JavaScript function that uses left shift to generate the mask for turning off a specified bit.

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