More things to say:

- Cute codes for 250 and 500:
`#define for_each(q, s) for(typeof(s.begin()) q=s.begin(); q!=s.end(); q++)`

struct EllysJuice

{

vector <string> getWinners(vector <string> players)

{

if (players.size() == 1) {

//special case with one turn, the only player wins.

return vector<string>(1, players[0] );

}

// Count how many times a player exists:

map<string,int> cnt;

for_each(p, players) {

cnt[*p]++;

}

// Add those guys with more than 2 instances to the result:

vector<string> res;

for_each(x, cnt) {

if (x->second >= 2) {

res.push_back(x->first);

}

}

sort(res.begin(), res.end());

return res;

}

};

`// long long once killed a kitten.`

typedef long long int64;

#define long int64

#define for_each(q, s) for(typeof(s.begin()) q=s.begin(); q!=s.end(); q++)

struct EllysFractions

{

long getCount(int N)

{

long pn = 0;

long res = 0;

set<int> primes;

for (int x=2; x<=N; x++) {

// is x prime?

bool isprime = true;

for_each(p, primes) {

isprime &= ( (x % (*p) ) != 0);

}

// Yes. Yes, it is...

if (isprime) {

pn++;

primes.insert(x);

}

// (2 raised to the pn-th) / 2 is the number

// of fractions for x!

res += (1LL << pn)/2;

}

return res;

}

};

#undef long - The problem in which you have to split numbers from 1-N in two parts and one must be denominator and one numerator is a interesting problem by itself. That's the problem I actually solved during the match. It took me 10 minutes to solve this problem and 100 minutes to figure out it was the wrong problem, so I spent most of the match trying to find out why was my solution returning such wrong value for N=100 (By the way, I see no reason at all not to allow a smaller number like 6 but larger than 5, in the example cases other than make people go wrong with this).
- Once I got desperate and it seemed like I was not going to solve the 500, I switched to 1000. And it seemed like I had solved the problem before and in TopCoder. But I had no idea how to solve it anymore and I could not find the old problem. So far the main suspect is round 306's div1 medium but it is actually a bit different. Maybe it was just a bugged Dejavu.

In my attempts to find the solution to it through google I found this: http://www.ripon.edu/academics/macs/summation/2010/articles/M.%20Madsen%20-%20Lights%20Out.pdf. Interesting. - Blogger has updated its interface and: BOY IT SUCKS ARGGGGGGGGGHHH IT SUCKS IT SUCKS IT SUCKS. Thanks I needed to get it out of my system.

Seriously, what is Google's problem? This is starting to look like I wasn't exaggerating when I said google was starting a war on color. Worse, google is going backwards now and blogger's interface is actually worse in small screens (buttons don't show up when you edit an entry) than before.

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