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Every year the cows hold an event featuring a peculiar version of hopscotch that involves carefully jumping from rock to rock in a river. The exciteme 阅读全文
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It is very hard to wash and especially to dry clothes in winter. But Jane is a very smart girl. She is not afraid of this boring process. Jane has dec 阅读全文
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Given N numbers, X1, X2, ... , XN, let us calculate the difference of every pair of numbers: ∣Xi - Xj∣ (1 ≤ i ＜ j ≤ N). We can get C(N,2) differences 阅读全文
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Farmer John is an astounding accounting wizard and has realized he might run out of money to run the farm. He has already calculated and recorded the 阅读全文
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King George has recently decided that he would like to have a new design for the royal graveyard. The graveyard must consist of several sections, each 阅读全文
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Some positive integers can be represented by a sum of one or more consecutive prime numbers. How many such representations does a given positive integ 阅读全文
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As you very well know, this year's funkiest numbers are so called triangular numbers (that is, integers that are representable as , where k is some po 阅读全文
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One day a highly important task was commissioned to Vasya — writing a program in a night. The program consists of n lines of code. Vasya is already ex 阅读全文
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This problem is given in two versions that differ only by constraints. If you can solve this problem in large constraints, then you can just write a s 阅读全文
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Kefa wants to celebrate his first big salary by going to restaurant. However, he needs company. Kefa has n friends, each friend will agree to go to th 阅读全文