sqlite3, 257 bytes

Result

WA

Code [DL]

WITH RECURSIVE lines(x, line, remain) AS (
  SELECT 1, substr(v, 0, 8) AS line, substr(v, 9) AS remain FROM i
  UNION ALL
    SELECT x + 1, substr(remain, 0, 8) AS line, substr(remain, 9) AS remain
    FROM lines
    WHERE remain != ''
)
SELECT x FROM lines

stdin

10111001
00110110
10001000
00001111
00101101
00110111
11011100
11111000
00000001
00111110
11100100
01011011
00100100
11101000
10000001
00011011
10101011
11101100
11100111
00011100
01110101
01010011
11111101
00001010
00010110
11101011
01011000
00000000
11001101
01011011
10111110
01101001
01001110
11011111
01011001
00100010
00010101
00000110
01000010
01000001
10011001
01111000
00001000
01111010
10101111
11010010
11100111
00000011
00010001
00111101

stdout

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stderr

strace