Golang program to check if k’th bit is set for a given number or not.

Examples

Consider n = 20(00010100), k = 3

So, the result after turning off the 3^rd bit => 00010000 & (1 << (4-1)) != 0

Approach to solve this problem −

Step 1 − Define a method, where n and k would be the arguments, returns type is int.

Step 2 − Perform AND operation with n & (1<<(k-1)).

Step 3 − If obtained number is not 0 then K^th of n is set else not set.

Example

package main
import (
   "fmt"
   "strconv"
)
func CheckKthBitSet(n, k int) int {
   return n & (1 << (k-1))
}
func main(){
   var n = 20
   var k = 3
   fmt.Printf("Binary of %d is: %s.\n", n, strconv.FormatInt(int64(n), 2))
   flag := CheckKthBitSet(n, k)
   if flag !=0 {
      fmt.Printf("%d rd bit of %d is aleady set.\n", k, n)
   } else {
      fmt.Printf("%d rd bit of %d is not set.\n", k, n)
   }
}

Output

Binary of 20 is: 10100.
3 th bit of 20 is aleady set.