Hello,

Yesterday I was solving this contest: 2015 Syrian Private Universities Collegiate Programming Contest, then I leave it to sleep.

Today I return to solve the rest of the problems, but I faced strange problem, I asked many friends to open any problem from this contest and they can open them, but for me I have the message in the bottom-right corner :(.

Message: Can't download contest descriptor from external storage. Are you sure you have at least one contest release?

Can any one tell me why this happen to me?

Hello everyone,

Today while I am proceeding in ladder C from a2oj.com I faced "Statement is not available." in this problem 388A - Fox and Box Accumulation, I hope this will be fixed soon.

Thank you MikeMirzayanov for the great Codeforces and I hope for it to dominate the first place among competitive programming sites all the time.

Peace,

In today's contest problem B, I tried to hack this solution 19690271, but all my 4 attempts where unsuccessful, then I decided to automate the hacking process with writing C++ code to try large random input on 2 versions of this code one with long and one with int but unfortunately 30 minutes without any break in the infinite loop which search for the test case, so I will be very thankful to the person who would explain to me why?

Greetings.

There is any O(N LOG K) algorithm for longest not strictly increasing subsequence?

Example for longest not strictly increasing subsequence:

n = 3
a[] = {1, 1, 1}

Normal O(N LOG K) algorithm will give answer = 1. (Because it's work strictly increasing)

I need modified algorithm to give answer = 3.

Thanks in advance.

Hello everybody,

I have a really hard problem with Dynamic Programming Bottom-up (table method).

Someone told me I should first do Top-down, then construct the base case, then construct recursion tree, then convert the recursion tree to Directed Acyclic Graph, then do a topological sort on this graph.

But always I get stuck and I can't find the solution.

Can any one help me with good material or write a blog about this like PrinceOfPersia [Algorithm Gym].

Thanks in advance :D.

Hi everyone.

I hope you're having a good day.

As you see in the picture when I read double using scanf "%lf" specifier it's ok, but when I'm trying to print double using printf "%lf" specifier, I got zero as result, but when I use "%f" floating-point specifier give me the right result, can any one help me with this problem and tell me why?

My IDE: Code::Blocks 13.12

My compiler: GNU GCC Compiler.

Thanks in advance :D

Hello everyone.

Happy Eid Al Fitr to everyone who is celebrating ^_^.

Hi everyone.

I think we can spread the science over Codeforces community, by sharing our knowledge and experiences in our blog and in that way we learn and let others learn also :D.

I will start with something simple and I hope it will help you Codeforces members :D.

Did you know that [C++] got StringTokenizer like [Java], it's implemented as a function in STL <cstring> called strtok(char * str, char * delimiters) for more information.

Hello everyone.

Today, while I'm trying to solve this easy problem 404A - Valera and X,

I write this code 11264735 using cin.tie(0); and ios_base::sync_with_stdio(0); and I got a wrong answer on test 2, but when I removed them from my code 11264741 I got Accepted, why??

Hi everybody...

How are you ??

I have learnt a new move in c++ while reading an array, and I would like to share it with you my friends :).

Most of us while reading an array in contest he/she use this move:

int x[100005];
int i;
for(i=0;i<50;i++)
    scanf("%d", &x[i]);

We use &x[i] for point to the ith element in the array... look look look we just press shift + 7 and then write x[i]. oh that's make me so tired.

But look at this move...

int x[100005];
int i;
for(i=0;i<50;i++)
    scanf("%d", x+i); // I just press x + i only and for the same reason, that's make me comfortable. ^_^

If you got any lazy move like this please share it with us :).

I'm junior in computer science major and I've learnt about binary search tree, and when I finished I found there is a lot of trees in computer science, What is the most important trees for competitive programmers?

100155A - The New President

I tried with this problem with all my powers ... that's how I tried to solve the problem first I calculated the max from the first column x[i][0] and if there are two max's go to the second column x[i][1] and calculate the max between the two first max's ,, finally print the answer and the round 1 or 2 ...

If I miss any thing please help me .. :)

What is the complexity of this Code... Order of what?? please help me.

10022450

Many Thanks to Codeforces.