9 c m ......... 14 c d ...............1176 file
18 c m .........14 c d .............1680 file
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18 - 9 = 9 c m ........................1680 - 1176 = 504 file
1 c m .....504 : 9 = 56 file
9 c m ........56 x 9 = 504 file
14 c d ..........1176 - 504 = 672 file
1 c d ................672 : 14 = 48 file