my @mos = ('01', '02', '03', '04', '05', '06', '07', '08', '09',
            10, 11, 12);
...
my @thirtyone = ('01', '02', '03', '04', '05', '06', '07', '08', '09',
            10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 
            23, 24, 25, 26, 27, 28, 29, 30, 31);