package main
import (
"fmt"
"math/bits"
)
/*
GetMSBPosition returns the zero-based position of the most significant
set bit (MSB) in an unsigned 32-bit integer.
Examples:
1 -> 0
2 -> 1
8 -> 3
15 -> 3
Returns:
-1 if value is 0 (no bits are set).
*/
func GetMSBPosition(value uint32) int {
if value == 0 {
return -1
}
return bits.Len32(value) - 1
}
func main() {
testValues := []uint32{
0,
1,
2,
8,
15,
0x1234,
0x80000000,
}
for _, value := range testValues {
position := GetMSBPosition(value)
if position >= 0 {
fmt.Printf(
"Value: %d, MSB position: %d\n",
value,
position,
)
} else {
fmt.Printf(
"Value: %d, no bits are set\n",
value,
)
}
}
}
/*
run:
Value: 0, no bits are set
Value: 1, MSB position: 0
Value: 2, MSB position: 1
Value: 8, MSB position: 3
Value: 15, MSB position: 3
Value: 4660, MSB position: 12
Value: 2147483648, MSB position: 31
*/
