打印字符串中给出的字符数

Pre*_*rem -1 ruby ruby-on-rails data-structures

我有字符串"A3B2C3D4" 它应该在输出中打印如下

AAABBCCCDDDD
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如何在红宝石中实现这一目标?

Ale*_*kin 5

"A3B2C3D4".scan(/(\D+)(\d+)/).map { |c, i| c * i.to_i }.join
#? "AAABBCCCDDDD"
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