D. Zip-line 题目连接： http://www.codeforces.com/contest/650/problem/D Description Vasya has decided to build a zip…

D. How many trees? 题目连接： http://www.codeforces.com/contest/9/problem/D Description In one very old text file t…

B. Filya and Homework 题目连接： http://codeforces.com/contest/714/problem/B Description Today, hedgehog Filya went…

B. Seating On Bus 题目连接： http://www.codeforces.com/contest/660/problem/B Description Consider 2n rows of the se…

D. Count Good Substrings 题目连接： http://codeforces.com/contest/451/problem/D Description We call a string good, …

E. Different Subsets For All Tuples 题目连接： http://www.codeforces.com/contest/660/problem/E Description For a se…

B. Drazil and Tiles 题目连接： http://codeforces.com/contest/516/problem/B Description Drazil created a following p…

C. Four Segments 题目连接： http://codeforces.com/contest/14/problem/C Description Several months later Alex finall…

E. Beautiful Subarrays 题目连接： http://www.codeforces.com/contest/665/problem/E Description One day, ZS the Coder…

C. Polycarp at the Radio 题目连接： http://codeforces.com/contest/723/problem/C Description Polycarp is a music edi…

B. Vasya and Wrestling 题目连接： http://codeforces.com/contest/493/problem/B Description Vasya has become interest…

A. Bear and Game 题目连接： http://www.codeforces.com/contest/673/problem/A Description Bear Limak likes watching s…