41. There are 20 balls in total, and two people take turns to pick them. Each person can take 1 to 3 balls at a time, and the one who picks the last ball wins. The one who picks has a winning strategy. （Fill in “first” or “second”）
Solution
Answer: After
untranslated text:
将上面的文本翻译成英文，请保留源文本的换行和格式，直接输出翻译结果。
Translation:
Answer: After
untranslated text:
Translate the text above into English, please retain the source text's line breaks and format, and output the translation result directly.
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