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Minus character set used in the "[...]" represents a set of characters in, such as:
“[1-3]” —— 表示1到5中的任意一个字符，所以“<H[1-3]>”表示“<H1>”、“<H2>”或者“<H3>”
“[d-g]” —— 表示“d”、“e”、“f”或者“g”
If it is not used in the character set. "[...]", the character is an ordinary, ie minus:
“1-[1-3]” —— 表示“1-1”、“1-2”或者“1-3”
However, even in the character set. "[...]", the Quefei between successive characters, loses its special meaning:
“1[-1]” —— 表示“1-”或者“11”