Standard input is empty

Array
(
    [0] => a
    [1] => b
    [2] => c
    [3] => d
    [4] => e
    [5] => f
    [6] => g
    [7] => h
    [8] => i
    [9] => j
    [10] => k
    [11] => l
    [12] => m
    [13] => n
    [14] => o
    [15] => p
    [16] => q
    [17] => r
    [18] => s
    [19] => t
    [20] => u
    [21] => v
    [22] => w
    [23] => x
    [24] => y
    [25] => z
    [26] => aa
    [27] => ab
    [28] => ac
    [29] => ad
    [30] => ae
    [31] => af
    [32] => ag
    [33] => ah
    [34] => ai
    [35] => aj
    [36] => ak
    [37] => al
    [38] => am
    [39] => an
    [40] => ao
    [41] => ap
    [42] => aq
    [43] => ar
    [44] => as
    [45] => at
    [46] => au
    [47] => av
    [48] => aw
    [49] => ax
    [50] => ay
    [51] => az
    [52] => ba
)