Find the missing permutation: Difference between revisions
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(moved PHP below perl, addded Phix) |
m (→{{header|Phix}}: added a bit more explanation) |
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r = sq_sub(max(r)+'A',r) |
r = sq_sub(max(r)+'A',r) |
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puts(1,r&'\n') |
puts(1,r&'\n') |
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-- based on the notion that missing = sum(full)-sum(partial) would be true, |
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-- and that sum(full) would be like {M,M,M,M} rather than a mix of numbers. |
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-- the final step is equivalent to eg {1528,1530,1531,1529} |
-- the final step is equivalent to eg {1528,1530,1531,1529} |
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-- max-r[i] -> { 3, 1, 0, 2} |
-- max-r[i] -> { 3, 1, 0, 2} |
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-- to chars -> { D, B, A, C} |
-- to chars -> { D, B, A, C} |
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-- (but obviously |
-- (but obviously both done in one line) |
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-- 2: the xor trick |
-- 2: the xor trick |
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end for |
end for |
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puts(1,r&'\n') |
puts(1,r&'\n') |
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-- (relies on the missing chars being present an odd number of times, non-missing chars an even number of times) |
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-- 3: find least frequent letters |
-- 3: find least frequent letters |
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end for |
end for |
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puts(1,r&'\n') |
puts(1,r&'\n') |
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-- (relies on the assumption that a full set would have each letter occurring the same number of times in each position) |
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-- 4: test all permutations |
-- 4: test all permutations |
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if not find(r,perms) then exit end if |
if not find(r,perms) then exit end if |
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end for |
end for |
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puts(1,r&'\n') |
puts(1,r&'\n') |
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-- (relies on brute force(!) - but this is the only method that could be made to cope with >1 omission)</lang> |
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{{out}} |
{{out}} |
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<pre> |
<pre> |
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