天使
grep - perldoc.perl.org 有 一位大學教授,在物理考卷出一條他認為很滿意的考題:「有條老問題:『有多少隻小天使能在一根繡花針的針頭飛舞?』用以下的資料回答這問題:每隻小天使要有一個方圓和一顆金原子相同的圓圈跳舞。針頭是平面圓形,平面面績等於十萬顆銀原子的面績。請清楚寫明所有grep BLOCK LIST grep EXPR,LIST This is similar in spirit to, but not the same as, grep(1) and its relatives. In particular, it is not limited to using regular expressions. Evaluates the BLOCK or EXPR for each element of LIST (locally setting $_ to each el...
全文閱讀