列出所有網路遮罩長度 IP

package main

import (
 "fmt"
 "math"
 "net"
 "encoding/binary"
)

  func main() {
    var ii uint32 = 0
    for i:=1; i<33; i++ {
      ii += uint32(math.Pow(2, float64(32-i)));
      fmt.Print(i, " ", long2ip(ii), "  ", ii, "\n")
    }
  }

        func ip2long(ipstr string) uint32 {
          ip := net.ParseIP(ipstr)
          if ip == nil {  return 0   }

          return binary.BigEndian.Uint32(ip.To4())
        }

        func long2ip(ipLong uint32) string {
          ipByte := make([]byte, 4)
          binary.BigEndian.PutUint32(ipByte, ipLong)

          return net.IP(ipByte).String()
        }