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JavaScript - Turn off the kth bit of a given number

JavaScript Bit Manipulation: Exercise-9 with Solution

Write a JavaScript program to turn off the kth bit in a given number. Return the new 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:

const turn_Off_Kth_Bit = (n, k) => {
 if (typeof n!= "number") {
     return 'It must be number!'
     }
   return n & ~(1 << (k - 1))
 }
n = 30
k = 3
console.log(n + " in binary is " + n.toString(2))
console.log("Turning k'th bit off,"+" k = "+k);
result_n = turn_Off_Kth_Bit(n, k)
console.log(result_n + " in binary is " + result_n.toString(2))
n = 100
k = 6
console.log(n + " in binary is " + n.toString(2))
console.log("Turning k'th bit off,"+" k = "+k);
result_n = turn_Off_Kth_Bit(n, k)
console.log(result_n + " in binary is " + result_n.toString(2))

Sample 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:

Flowchart: JavaScript - Turn off the kth bit of a given number.

Live Demo:

See the Pen javascript-bit-manipulation-exercise-9 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

Returns the sum of an array, after mapping each element to a value using the provided function

Example:

const tips_sumBy = (arr, fn) =>
  arr.map(typeof fn === 'function' ? fn : val => val[fn]).reduce((acc, val) => acc + val, 0);

console.log(tips_sumBy([{ n: 2 }, { n: 4 }, { n: 6 }, { n: 8 }], o => o.n));
console.log(tips_sumBy([{ n: 1 }, { n: 3 }, { n: 5 }, { n: 7 }], 'n'));

Output:

20
16