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一、题目Notice that the number 123456789 is a 9-digit number consisting exactly the numbers from 1 to 9, with no duplication. Double it we will obtain 246913578, which happens to be another 9-digit number...

一、题目A number that will be the same when it is written forwards or backwards is known as a Palindromic Number. For example, 1234321 is a palindromic number. All single digit numbers are palindromic num...

一、题目A long-distance telephone company charges its customers by the following rules:Making a long-distance call costs a certain amount per minute, depending on the time of day when the call is made. Wh...

一、题目To evaluate the performance of our first year CS majored students, we consider their grades of three courses only: C - C Programming Language, M - Mathematics (Calculus or Linear Algebra), and E -...