EGYPT's blog

Problem 'E' Chip Play CF#74 Div2
By EGYPT, 13 years ago, In English
I get TLE on testcase 16 i think my algorithm is true but i need tips to improve the speed of the algorithm

some useful hints if you will help me:

1-I use recursive function but i make global varible called ct which count the steps .
2-I mark visited cell with '#' on the same matrix.
3-I make global variable called dr ,i save the last direction on it.
so   R RRL L and last direction L i will ignore the value of the cells RRL
4-Every iteration i pick cell and make recursive call on it,i make ct=0 and i send matrix by value not by reference.

if my approach totally wrong please tell me the true approach 

Click Here to see my code
Thanks in advanced.



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Exclusive or "Xor" range ?
By EGYPT, 13 years ago, In English

I ask if i can calculate xor  to all numbers in a specific range without using loop

for example if  i have 

start=3  
end =3211233432145321;

the result  start ^ start+1 ^ start+2 ^ start+3.........end-1^end

Thanks in advanced.

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what's the proof of this approach? Yandex Round 2_A
By EGYPT, 13 years ago, In English

Problem A


most competitors use this approach in this problem
check max between wight between low and high
so res=max(wight(low),wight(high).
then putting current =5
then loop while current<=high
get max between res and and wight(current) and wight(current-1)
then current=current*10

I know this algorithm work correctly but what's the proof 

for example if the range 1-783432
so the result max wight between (783432,500000,499999)

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out of Competition Rules
By EGYPT, 13 years ago, In English

Today I will Enter this contest as out of competition ,

I wan't to know if i can hack or not,
and i want to know my distribution "my room contain only out of competition people or not".
Thanks for clarification  

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