Hi all,

Today we would like to invite you to take part in round #83 inspired by the ACM practice sessions last year when Dima was visiting the German University in Cairo (GUC).

We have composed the problemset about life in Egypt and the GUC. Hope you will like it :)

The points for the problems in Div 1 & 2 will be: 500-1000-1500-2000-2500.

The writers of the problems are Dima and myself.

We would like to thank RAD, Connector, it4.kp, Delinur, and MikeMirzayanov, who greatly helped in preparing this contest.

We wish you a pleasant, educational and successful contest!

unregister, sorry! :D"The rating won't change unless you make at least one submission

or hackingattempt."If I undesrtood correctly, doesn't seem really fair...

[Also, there is less chances that in just 15 minutes you will understand the question, then find the corner cases and verify others code.]

How about solving a BIG problem and everyone contributing a little in it.

Just in 2 hrs solving a BIG problem, doesn't it sound interesting.?

I appeal all red coders to think about it, is it possible for you guys to formulate one such problem and distribute it among all the people , so that everyone contribute his part , and finally a big task is done.

[this will give more satisfaction and fun!]

......

Just a thought :DI sent Java solution for problem A and I got "runtime error", I sent again the same solution few minutes after and I got Accepted, but I guess some points are lost for "wrong" submission.

I noticed the message during the contest that there was some problem with "runtime error" with Java solutions on task A. After the contest I saw that the my first "runtime error" solution was tested again, this time with "Accepted" but I think the points remained the same...

I enjoyed the problems :)

ORORna na na na!

p *= (long double)a/b; instead of

p /= b;

p*=a; ?

_{h}team...===

Будет ли контест рейтинговым?

What if the first is correct submision, but not the second?

How score is calculated?

So, it is a good thing to know.

I would assume there is a penalty for resubmision, but I wonder, what happens, if 1st submision is correct, but not the second...

is it a Combinations problem?

7

1 2 3 4 8 16 32

in B (div 2) is Yes?

if we use x=65535

_{10}=11111111 11111111_{2}we will get x*x=4294836225_{10 }= 11111111 11111110 00000000 00000001 which fits in 32 bits3 3 5 12

the answer should be "YES".

I hacked 5 solutions with this case.

(Edited)

^{2}=49 doesn't fit in 4 bits, so the answer is "Yes".^{2}x, such thatxfits in some typei(ina_{i}bits) andx·xdoes not fit in some other typej(ina_{j}bits) wherea_{i}<a_{j}, then Tuftuf will stop using Gava."a_{i , }a_{j}) then the answer is "Yes".someother type"._{2})^{2}does not fit into 3 bits I think._{10}=11_{2}which fits in 2 bits, we will get x^{2}=9_{10}=1001_{2}, which doesn't feet in 3 bits.`[9, 6, 15, 18, 2, 14, 20, 14, 12, 12] [29, 47, 9, 49, 25, 17, 41, 35, 9, 40] [19, 50, 34]`

5

0 0 3 0 3 3 0 3

6 0 9 0 9 3 6 3

6 6 9 6 9 9 6 9

0 6 3 6 3 9 0 9

4 4 5 4 5 5 4 5

It gives 1.0571428571428572

obviously the answer is 1