{"published":"2008-05-02 14:20:01","version":"1.0","url":"https://nishiohirokazu.hatenadiary.org/entry/20080502/1209705601","provider_name":"Hatena Blog","type":"rich","blog_title":"\u897f\u5c3e\u6cf0\u548c\u306e\u306f\u3066\u306a\u30c0\u30a4\u30a2\u30ea\u30fc","categories":["cpp"],"author_name":"nishiohirokazu","height":"190","author_url":"https://blog.hatena.ne.jp/nishiohirokazu/","html":"<iframe src=\"https://hatenablog-parts.com/embed?url=https%3A%2F%2Fnishiohirokazu.hatenadiary.org%2Fentry%2F20080502%2F1209705601\" title=\"optional\u3092\u4f7f\u3063\u3066\u307f\u308b - \u897f\u5c3e\u6cf0\u548c\u306e\u306f\u3066\u306a\u30c0\u30a4\u30a2\u30ea\u30fc\" class=\"embed-card embed-blogcard\" scrolling=\"no\" frameborder=\"0\" style=\"display: block; width: 100%; height: 190px; max-width: 500px; margin: 10px 0px;\"></iframe>","title":"optional\u3092\u4f7f\u3063\u3066\u307f\u308b","provider_url":"https://hatena.blog","width":"100%","image_url":null,"blog_url":"https://nishiohirokazu.hatenadiary.org/","description":"\u3064\u3044\u3046\u3063\u304b\u308a\u30aa\u30fc\u30d0\u30fc\u30d5\u30ed\u30fc\u3057\u3066\u3057\u307e\u3063\u30660\u70b9\u3001\u3068\u3044\u3046\u306e\u304c\u983b\u51fa\u306f\u307e\u308a\u30d1\u30bf\u30fc\u30f3\u306a\u306e\u3067\u3001optioal\u3092\u4f7f\u3063\u3066Maybe\u30e2\u30ca\u30c9\u7684\u306a\u6574\u6570\u578b\u3092\u4f5c\u308c\u3070\u3044\u3044\u3093\u3058\u3083\u306a\u3044\u304b\u3068\u601d\u3063\u305f\u3002\u3068\u3044\u3046\u308f\u3051\u3067\u300c\u639b\u3051\u7b97\u306f\u30aa\u30fc\u30d0\u30fc\u30d5\u30ed\u30fc\u3059\u308b\u53ef\u80fd\u6027\u304c\u3042\u308b\u300d\u3068\u3044\u3046\u3053\u3068\u3092\u5fd8\u308c\u305a\u306b\u3044\u3089\u308c\u308b\u578b\u304c\u3067\u304d\u305f\u3002if(x)\u3067\u78ba\u8a8d\u3057\u3066\u304b\u3089*x\u3057\u306a\u3044\u3068\u5024\u3092\u53d6\u308a\u51fa\u305b\u306a\u3044\u306e\u3067\u300c\u30aa\u30fc\u30d0\u30fc\u30d5\u30ed\u30fc\u3057\u3066\u3044\u308b\u304b\u3082\u3057\u308c\u306a\u3044\u6574\u6570\u300d\u304b\u3089\u300c\u30aa\u30fc\u30d0\u30fc\u30d5\u30ed\u30fc\u3057\u3066\u3044\u306a\u3044\u3053\u3068\u3092\u78ba\u8a8d\u300d\u3057\u3066\u304b\u3089\u300c\u30aa\u30fc\u30d0\u30fc\u30d5\u30ed\u30fc\u3057\u3066\u3044\u306a\u3044\u6574\u6570\u578b\u300d\u306b\u5909\u63db\u3057\u3066\u4f7f\u3046\u3053\u3068\u306b\u306a\u308b\u3002 #include<boost/optional.hpp> using namespace boost; typedef long lo\u2026"}