At the school where Vasya is studying, preparations are underway for the graduation ceremony. One of the planned performances is a ball, which will be attended by pairs of boys and girls. Each class must present two couples to the ball. In Vasya’s class, a boys and b

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Polycarp remembered the 2020-th year, and he is happy with the arrival of the new 2021-th year. To remember such a wonderful moment, Polycarp wants to represent the number n as the sum of a certain number of 2020 and a certain number of 2021. For example, if: n=4041, then

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Problem : You are given an integer n. Check if n has an odd divisor, greater than one (does there exist such a number x (x>1) that n is divisible by x and x is odd). For example, if n=6, then there is x=3. If n=4, then such a number does not exist. Input : The first line

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