package main
import (
"fmt"
)
func printBits(value uint64, width int) {
for i := width - 1; i >= 0; i-- {
mask := uint64(1) << uint(i)
if value&mask != 0 {
fmt.Print("1")
} else {
fmt.Print("0")
}
}
}
func exactBitSet(pos1, pos2 int, value uint64) bool {
if pos1 < 0 || pos2 < 0 || pos1 >= 64 || pos2 >= 64 {
return false
}
if pos1 == pos2 {
return false
}
mask := (uint64(1) << uint(pos1)) | (uint64(1) << uint(pos2))
return value == mask
}
func main() {
tests := []struct {
value uint64
x, y int
width int
}{
{0b1000010000, 4, 9, 10},
{0b0010000010, 1, 7, 10},
{0b0000100100, 2, 5, 10},
{0b1000010000, 3, 9, 10},
{0b1001010000, 4, 9, 10},
{0b1111111111, 4, 9, 10},
{0b0000000000, 4, 9, 10},
{0b1000010000, 4, 8, 10},
{1, 0, 0, 1},
{1, 0, 1, 1},
{0, 1, 1, 1},
}
for _, t := range tests {
printBits(t.value, t.width)
fmt.Printf(" bits(%d, %d) -> %v\n",
t.x, t.y, exactBitSet(t.x, t.y, t.value))
}
}
/*
OUTPUT:
1000010000 bits(4, 9) -> true
0010000010 bits(1, 7) -> true
0000100100 bits(2, 5) -> true
1000010000 bits(3, 9) -> false
1001010000 bits(4, 9) -> false
1111111111 bits(4, 9) -> false
0000000000 bits(4, 9) -> false
1000010000 bits(4, 8) -> false
1 bits(0, 0) -> false
1 bits(0, 1) -> false
0 bits(1, 1) -> false
*/
