>>91
Ruby で

# 数字の配列の配列。改行は削除
nums = <<"EOT".lines( chomp: true ).map{ |str| str.split( "," ).map( &:to_i ) }
1,1,1,1,2,2,2,3,3,4
1,2,3,4,5,5,4,3,2,1
3,1,4,1,5,9,2,6,5,3,5
EOT

results = nums.each_with_object( [ ] ) do |ary, results|
uniq_ary = ary.uniq # 重複排除
uniq_ary.sort! # ソート

res = -1
uniq_ary.each do |num|
if ary.count( num ) == 1
res = num; break
end
end
results.push res
end

p results #=> [4, -1, 2]