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Omar_Mekkawy's blog

By Omar_Mekkawy, history, 3 years ago, In English,

i had this conversation with the Judge in the middle of the contest: http://imgur.com/a/HdXPc

"Masha writes all progression terms one by one onto the board (including repetitive) while condition |bi| ≤ l is satisfied (|x| means absolute value of x). There is an exception: if a term equals one of the "bad" integers, Masha skips it (doesn't write onto the board) and moves forward to the next term."

So masha writes on the board while |bi|<=l according to my English. Not masha generates the sequence while |bi|<=l and writes if the other conditions are satisfied.

similar approach sentence: i should go up while the light is on, does that mean if the light goes off and then on again i don't go up?

according to the problem settler, he should "STOP GENERATING" the sequence when |bi|<=l , which is not mentioned in the problem statement.

i sent the wrong solution as a test, after wasting the whole contest trying to find if my solution has something wrong,

in case you don't know why this would matter

test case: 10 0 9 1 1 answer : inf

judge's answer: 0

i hope this will be addressed.

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By Omar_Mekkawy, history, 4 years ago, In English,

Today i was trying to solve a problem , but at some point i couldn't calculate something , and i couldn't prove my solution,

so i decided to read the editorial , sadly the editorial had no details at all , while for problem authors those details may be obvious or intuitive, for some they aren't and those details are essential and crucial,

is there anyway we could re-publish some of the editorials with details and formality upon community requests ? even in a private way if we'll distribute the effort...

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By Omar_Mekkawy, history, 4 years ago, In English,

Regarding finding articulation points, we use dfs order (dfs time) , to know the exact time of visiting this node, taking the maximum time of my children to assign if i'm articulation , and the minimum is returned to my parent,

i tried to switch the dfs order to using depth , meaning that the dfs order of the node is it's depth and i take the maximum depth for myself and return the minimum depth to my parent, but it hasn't been working i've been getting wrong answers,

Should it work or not, and if not could you provide the test case?

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By Omar_Mekkawy, history, 4 years ago, In English,

Hacker rank code spirit starts 30 mins earlier than round 349 and lasts for 24 hours, can't round 349 start earlier 3 hours?

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By Omar_Mekkawy, 5 years ago, In English,

http://ideone.com/uzJr07 shouldn't this case time limit? a=536870914 b=2 ,, i just found out, please add this case as i used bitmask which shouldn't pass at all! also this case a=536870913 b=1 http://codeforces.com/contest/495/submission/9120923 Problem B Div2 Round 282

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By Omar_Mekkawy, 5 years ago, In English,

in the editorial it's mentioned that No solution exists if 3x < y. in case of n=2.

can anyone please tell me why is that true? and in my accepted solution , in case of n=2 i iterated 10^6 and assumed that my 3 sorted numbers are the first,second,and third number , can any one please tell me why did this solution pass and we didnt have to try all the permutations for the 3 numbers with the 4th generated one?

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