Revenge of the Clocks
View as PDFThere are  clocks, arranged in a 
 array. They are labelled:
A B C
D E F
G H I
Each clock is set to either one o'clock, two o'clock, three o'clock, …
or twelve o'clock.
There are nine possible moves, numbered from  to 
. Each move advances
a certain set of clocks by 
 hour. The moves and their corresponding
sets of clocks are:
1 ABDE
2 ABC
3 BCEF
4 ADG
5 BDEFH
6 CFI
7 DEGH
8 GHI
9 EFHI
We wish to know the shortest sequence of moves that will restore all the
clocks to twelve o'clock.
For example, suppose , 
, and 
 are initially set to eleven o'clock, 
,
, and 
 are set to twelve o'clock, and 
, 
, and 
 are set to ten
o'clock. Then, doing move 
 once and move 
 twice resets all the
clocks.
Input Specification
 lines, containing one integer each, the initial states of clocks 
, 
,
, 
, 
, 
, 
, 
, and 
, respectively, where 
 denotes one o'clock, 
denotes two o'clock, and so on.
Output Specification
 lines, containing one integer each. Line 
 should contain the
number of times to do move 
 in the shortest possible sequence of
moves.
Sample Input
11
11
11
12
12
12
10
10
10
Sample Output
0
1
0
0
0
0
0
2
0
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