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题目来源：http://codeforces.com/problemset/problem/230/A Kirito is stuck on a level of the MMORPG he is playing now. To move on in the game, he's got to de 阅读全文
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题目来源：http://codeforces.com/problemset/problem/479/A Petya studies in a school and he adores Maths. His class has been studying arithmetic expressions. 阅读全文
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题目来源：http://codeforces.com/problemset/problem/131/A wHAT DO WE NEED cAPS LOCK FOR? Caps lock is a computer keyboard key. Pressing it sets an input mod 阅读全文
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题目来源：http://codeforces.com/contest/158/problem/B After the lessons n groups of schoolchildren went outside and decided to visit Polycarpus to celebrat 阅读全文
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题目来源：http://codeforces.com/problemset/problem/110/A Petya loves lucky numbers. We all know that lucky numbers are the positive integers whose decimal 阅读全文
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题目来源：http://codeforces.com/problemset/problem/266/B During the break the schoolchildren, boys and girls, formed a queue of n people in the canteen. In 阅读全文
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题目来源：http://codeforces.com/problemset/problem/116/A Linear Kingdom has exactly one tram line. It has n stops, numbered from 1 to n in the order of tra 阅读全文
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题目来源： http://codeforces.com/problemset/problem/122/A Petya loves lucky numbers. Everybody knows that lucky numbers are positive integers whose decimal 阅读全文