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Parentheses
P31111
Statement
html
Given a sequence made up of only ‘(’ and ‘)’,
tell if the parentheses close correctly.
Input
Input consists of a sequence of parentheses.
Output
Print “yes” or “no”,
depending on whether the parentheses close correctly or not.
About statements
The official statement of a problem is always the one
in the PDF document. The HTML version of the statement
is also given to help you, but may contain some content
that is not well displayed. In case of doubt, always use the PDF.