#!ruby
 
def tree_sub( data, cd, nst, str = '' )
	cds = []
	data.each_with_index{|n,idx|
		cds << idx	if n == cd
	}
	str2 = str + ( (cds.size > 1)? "│ " : "  " )
	cds.each_with_index{|x,idx|
		print str, (cds.size - 1 <= idx)? "└" : "├", "─ #{x}\n"
		tree_sub( data, x, nst + 1, str2 )
	}
end
 
def tree( data )
	cd = data.index( -1 )
	puts cd
	tree_sub( data, cd, 0 )
end
 
 
	tree( [1, 2, -1, 0, 0, 1, 1, 2] )
	puts
	tree( [-1, 0, 1, 2, 3, 2] )
 
 

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