atsuoishimoto https://blog.hatena.ne.jp/atsuoishimoto/ atsuoishimoto's diary https://atsuoishimoto.hatenablog.com/ Python ふとこちらの記事を拝見して、頭に浮かんだことをメモってみる。id:aroma_blackさんの [y for x,y in enumerate(seq) if seq[:x+1].count(y) == 1] や、id:cocoatomoさんの [x for i, x in enumerate(a) if i == a.index(x)] でも良いんだけど、あえて別解を探すと：Python2.7/3なら import collections list(collections.OrderedDict((x,None) for x in seq).keys()) 一番素直で速いのは filter(… 190 <iframe src="https://hatenablog-parts.com/embed?url=https%3A%2F%2Fatsuoishimoto.hatenablog.com%2Fentry%2F20110513%2F1305279801" title="uniq()あれこれ - atsuoishimoto&#39;s diary" class="embed-card embed-blogcard" scrolling="no" frameborder="0" style="display: block; width: 100%; height: 190px; max-width: 500px; margin: 10px 0px;"></iframe> Hatena Blog https://hatena.blog 2011-05-13 18:43:21 rich https://atsuoishimoto.hatenablog.com/entry/20110513/1305279801 1.0 100%