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题目来源：http://codeforces.com/problemset/problem/236/A Those days, many boys use beautiful girls' photos as avatars in forums. So it is pretty hard to te 阅读全文
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题目来源：http://codeforces.com/problemset/problem/266/A There are n stones on the table in a row, each of them can be red, green or blue. Count the minimu 阅读全文
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题目来源：http://codeforces.com/problemset/problem/96/A Petya loves football very much. One day, as he was watching a football match, he was writing the pl 阅读全文
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题目来源：http://codeforces.com/problemset/problem/339/A Xenia the beginner mathematician is a third year student at elementary school. She is now learning 阅读全文
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题目来源：http://codeforces.com/problemset/problem/263/A You've got a 5 × 5 matrix, consisting of 24 zeroes and a single number one. Let's index the matrix 阅读全文