perl 날짜 계산하기..

#!/usr/bin/perl -w

use strict ;
use Date::Calc qw(Add_Delta_Days) ;

my ( $todayd, $todaym, $todayy ) = (localtime)[3..5] ;
$todaym += 1 ;
$todayy  += 1900 ;

my ($yesty,$yestm,$yestd) = Add_Delta_Days($todayy,$todaym,$todayd, -1) ;

어제 구하기..