ä»åã®è©± 以åãVisitorãã¿ã¼ã³ã§åã«ããswitchãifå¤å®ãæ¶ãã¨ããè¨äºãæ¸ãã¾ãããååã®ããæ¹ã«å¾ãã°Visitorãã¿ã¼ã³ã使ãã°switchæãæ¶ãã¦åå®å ¨ã«ãããã¨ãã§ãã¾ããã ãã ãããããå®é使ããããã®ãï¼ãã¨ããã¨æ£ç´ãªã¨ããå¾®å¦ã§ããã ããããããã§ä»åã¯ã妥åããã¦ã§ããã ãå®å ¨ã«ããªãã使ãåæãä¿ã¤ãæ¹æ³ãç´¹ä»ãã¾ãã ååã®ãããã åé¡ã¨ããã³ã¼ã Visitorãã¿ã¼ã³ã§åã«ããswitchãifå¤å®ãæ¶ãã§ç´¹ä»ããã³ã¼ãã®ããããã§ãã ä½ãéè¦ãã¦ãããã¨ããã¨ãåã®ç¶²ç¾ æ§ãä¿è¨¼ããããã§ããããããã¼ã¿æ§é 群ãä»ã®ãã¼ã¿æ§é ã«å¤æããã¨ããªã©ãswitchã使ã£ããã¼ã¿ã³ãããã³ã°ã§è¨è¿°ãããã¨ãã§ãã¾ãã using System; namespace Visitors.Samples { public static class C