Category: math
The problem is from codeforces: http://www.codeforces.com/problemset/problem/69/A The tests were not strong because I failed at the 81-th test on the first submission using a wrong algorithm (actually I mis-understood …
The problem is from codeforces: http://www.codeforces.com/problemset/problem/137/B It took me several attempts to get it right for this problem although it is not difficult. The problem is find out how …
The problem is from codeforces: http://www.codeforces.com/problemset/problem/158/A It is summer. The temperature today in Sheffield is 25 degree. I got to say, I feel a bit sleepy in the afternoon. …
The problem is from codeforces: http://www.codeforces.com/problemset/problem/4/A The problem is so easy that you might even falls into the trap (you might think judging if it is even or odd). …
The problem is from codeforces: http://www.codeforces.com/problemset/problem/102/B The input can be very large, you might wonder to use long arithmetic via arrays. However, it might be easier than you think. …