use std::f64;
// Function to find the position of the first set bit
fn find_first_set_bit_position(num: i32) -> i32 {
// Edge case: If the number is 0, there are no set bits
if num == 0 {
return 0; // Return 0 to indicate no set bit
}
/*
* num & -num isolates the lowest set bit.
* log2(...) gives the zero-based index of that bit.
*/
((num & -num) as f64).log2() as i32
}
fn main() {
let num = 4224; // Binary: 0001 0000 1000 0000
// Find and display the position of the first set bit
let position = find_first_set_bit_position(num);
if position == 0 {
println!("The number has no set bits (it's 0).");
} else {
println!("The position of the first set bit is: {}", position);
}
}
/*
run:
The position of the first set bit is: 7
*/
