当前你的浏览器版本过低,网站已在兼容模式下运行,兼容模式仅提供最小功能支持,网站样式可能显示不正常。
请尽快升级浏览器以体验网站在线编辑、在线运行等功能。

建议使用的浏览器:

谷歌Chrome 火狐Firefox Opera浏览器 微软Edge浏览器 QQ浏览器 360浏览器 傲游浏览器

2372:D++ Again

题目描述
The language D++, that was perfected by the participants of our March competition, continues improving. Its founders try to make the syntax as clear as it is possible in order to make the programming simpler in the future.
Of course, some minimal set of rules is to stay without changes. Your program is to check the observance of rules, concerning the arrangement of brackets and comments.

A text of a correct D++ program contains a symbol part, arithmetic expressions and comments. Comments may appear everywhere and may contain every symbol. A comment is always opened by a pair of symbols "(*" and is closed by a pair of symbols "*)". Each comment must be closed. An arithmetic expression in D++ is always opened by "(", is closed by ")" and may contain any of the following symbols: "=+-*/0123456789)(" and, surely, comments. No spaces in arithmetic expressions are allowed, though a carriage return may occur. You may run across embedded brackets in an arithmetic expression. In this case these brackets are to be balanced. It means that "((1)))" as well as "(23))((+)" are not correct arithmetic expressions. An arithmetic expression is correct if and only if brackets placed correctly. At last, all the rest of the program text (the result of rejection of all comments and arithmetic expressions from the initial text of the program) may contain every symbol excluding "(" and ")".
We would like to especially notice that the spaces are posiible anywhere in a text of a program except when apppeearing in arithmetic expressions.
输入解释
Some text is written in the standard input. There are not more than 10 000 symbols in the text. There may be Latin letters, digits, brackets, symbols of arithmetic operations and the symbols "end of line" and "carriage return".
输出解释
Your program should write "YES" to the output if the introduced text is a correct D++ program, and "NO" otherwise.
输入样例
Hello, here is a sample D++ program. It contains some arithmetical expressions like
(2+2=4), (2+-/*) and ((3+3)*3=20(*this is not true, but you don't have to verify it :-) *)+8)
 (* the closing bracket in the previous comment is also in order, since this bracket
does not belong to any arithmetical expression*)
输出样例
YES

该题目是Virtual Judge题目,来自 北京大学POJ

源链接: POJ-2372

最后修改于 2020-10-29T06:30:56+00:00 由爬虫自动更新

共提交 0

通过率 --%
时间上限 内存上限
1000 65536