/*
zeroBitsEveryStep(number, step)
-------------------------------
Zeros every `step`-th bit (0-based from LSB)
but only if that bit is currently 1.
Example:
number = 536_870_911
step = 3 → zero bits 0, 3, 6, 9, ...
*/
fun zeroBitsEveryStep(number: Int, step: Int): Int {
var result = number
var pos = 0
while (pos < 32) {
val mask = 1 shl pos
// If the bit is 1, zero it
if ((result and mask) != 0) {
result = result and mask.inv()
}
pos += step
}
return result
}
/*
printBinary(n)
--------------
Prints a 32-bit binary representation of an integer.
*/
fun printBinary(n: Int) {
val s = n.toString(2).padStart(32, '0')
val grouped = s.chunked(4).joinToString(" ")
println(grouped)
}
fun main() {
val number = 536_870_911 // 0001 1111 1111 1111 1111 1111 1111 1111
val step = 3 // zero bits 0, 3, 6, 9, ...
println("Original number in binary:")
printBinary(number)
val result = zeroBitsEveryStep(number, step)
println("\nNumber after zeroing every $step bits (only if bit was 1):")
printBinary(result)
println("\nResult as integer: $result")
}
/*
run:
Original number in binary:
0001 1111 1111 1111 1111 1111 1111 1111
Number after zeroing every 3 bits (only if bit was 1):
0001 0110 1101 1011 0110 1101 1011 0110
Result as integer: 383479222
*/
