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Description Little Nastya has a hobby, she likes to remove some letters from word, to obtain another word. But it turns out to be pretty hard for her, 阅读全文
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Description Igor found out discounts in a shop and decided to buy n items. Discounts at the store will last for a week and Igor knows about each item 阅读全文
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Description Polycarp is crazy about round numbers. He especially likes the numbers divisible by 10k. In the given number of n Polycarp wants to remove 阅读全文
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Description In Berland each high school student is characterized by academic performance — integer value between 1 and 5. In high school 0xFF there ar 阅读全文