alias amtopm {
  var %hH = $gettok($1,1,58)
  var %nN = $gettok($1,2,58)
  if (%hH <= 12 && %hH <= 12) {
    var %rslt = $calc(%hH + 12)
    return $+(%rslt,:,%nN) 
  }  
}
alias pmtoam {
  var %hH = $gettok($1,1,58)
  var %nN = $gettok($1,2,58)
  if (%hH >= 12 && %hH <= 24) {
    var %rslt = $calc(%hH - 12)
    if ($len(%rslt) == 1) { return $+(0,%rslt,:,%nN) } 
    else { return $+(%rslt,:,%nN) }
  } 
}