#!/usr/bin/env tclsh8.6

while {[gets stdin line] >= 0} {
  if {$line eq ""} continue
  set len [string length $line]
  lappend list [scan $line %b]
}

set oxy $list
set mask [expr {2**($len-1)}]
while {[llength $oxy] > 1} {
  # puts "mask = $mask  length = [llength $oxy]"
  # Which bit is most common?
  set zero 0; set one 0
  foreach n $oxy {
    if {($n & $mask) > 0} {incr one} else {incr zero}
  }
  if {$one >= $zero} {set keepbit $mask} else {set keepbit 0}

  # Discard undesirables.
  set new [list]
  foreach n $oxy {
    if {($n & $mask) == $keepbit} {lappend new $n}
  }
  set oxy $new

  # Don't forget:
  set mask [expr {$mask / 2}]
}
puts "oxy = [lindex $oxy 0]"

set co2 $list
set mask [expr {2**($len-1)}]
while {[llength $co2] > 1} {
  # puts "mask = $mask  length = [llength $co2]"
  # Which bit is most common?
  set zero 0; set one 0
  foreach n $co2 {
    if {($n & $mask) > 0} {incr one} else {incr zero}
  }
  if {$zero <= $one} {set keepbit 0} else {set keepbit $mask}

  # Discard undesirables.
  set new [list]
  foreach n $co2 {
    if {($n & $mask) == $keepbit} {lappend new $n}
  }
  set co2 $new

  # Don't forget:
  set mask [expr {$mask / 2}]
}
puts "co2 = [lindex $co2 0]"
puts "product = [expr {[lindex $oxy 0] * [lindex $co2 0]}]"