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JavaScript - Check if kth bit is set or not for a number

JavaScript Bit Manipulation: Exercise-11 with Solution

Write a JavaScript program to check whether the kth bit is set or not in a given number. Return true if the kth bit is set otherwise false.

In a binary representation the presence of a non-zero value indicates that the k'th bit is set.

Test Data:
(33, 1) -> true
Explanation:
Binary format of 33 is -> 100001
K =1 -> kth bit is 1 [Non-zero value indicates that the k'th bit is set.]
(33, 2) -> false
Explanation:
Binary format of 33 is -> 100001
K =2 -> kth bit is 0 [Zero value indicates that the k'th bit is not set.]

Sample Solution:

JavaScript Code:

const turn_On_Kth_Bit = (n, k) => {
 if (typeof n!= "number") {
     return 'It must be number!'
     }
   return (n & (1 << (k - 1))) != 0;
 }
n = 33
k = 1
console.log(n + " in binary is " + n.toString(2))
console.log("k = "+k);
result_n = turn_On_Kth_Bit(n, k);
console.log("Check kth bit is set or not in the said number! " + result_n)
n = 33
k = 2
console.log(n + " in binary is " + n.toString(2))
console.log("k = "+k);
result_n = turn_On_Kth_Bit(n, k);
console.log("Check kth bit is set or not in the said number! " + result_n)

Sample Output:

33 in binary is 100001
k = 1
Check kth bit is set or not in the said number! true
33 in binary is 100001
k = 2
Check kth bit is set or not in the said number! false

Flowchart:

Flowchart: JavaScript - Check if kth bit is set or not for a number.

Live Demo:

See the Pen javascript-bit-manipulation-exercise-11 by w3resource (@w3resource) on CodePen.


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Next: Position of the rightmost set bit of a number.

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