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Wrong

HUMONGOUS QUERY can be solved by generating all combinations and pruning.

I wrote about it here.

My solution passed in 0.51 s

MONSTER, KILLKTH — the same with optimisations
HYHUMOQ — you can also memoize solutions for both parts and then iterate through solutions of diophantine equations
SQRGOOD — use binary search with square decomposition from paper and then decrease search interval by approximation

Also it seems KILLJEE KTH LETTER can be solved with trie according to this comment

In killkth, I got 100pts AC with a linear traversal on the sorted list of nodes without binary search, and that too in 0.25s(Did binary search later and got the same execution time). Asserted and found out that I'm visiting atmost 20 nodes per query, via linear search, which is surprising to me.

Killing Monster can be solved using square root + Sum over subsets also

Here is my solution:https://www.codechef.com/viewsolution/17063146

Well , This was how I calculated X

int zero = 0 , one = 0 ;
int z = (int) str.size() ;
for (int j=z-1;j>=0;j--)
{
	if (str[j] == '0')
	{
		zero += (1 + one) ;
	}else
	{
		one += zero ;
	}
}

The value of X = one .

X=(A+1)*(C+1)-1 + B*D.
A=10/1010 type in left string.
B=1/101 type in left string.
C=10/1010 type in right string.
D=0/010 type in right string.

For each type A seq, we can join it to a type C seq. We add +1 to each of these values to account for empty seq and subtract -1 finally to account for taking empty seq from both sides.

For each B seq, we must combine it with some type D seq. So this contributes B*D sequences.

Here :

if (v.back() <= rs) 
{
 
    rs -= v.back(); 
    two.pb(v.back()); 
			
}

I changed it to :

if (v.back() <= rs && rs - v.back() != x) 
{
 
    rs -= v.back(); 
    two.pb(v.back()); 
			
}

And it passed.

LINK

They are already out

i don't think that ,it is can be solved with trie. There are 2^18 queries ,it is a one problem ,and also trie it is not good to this problem,because you don't uses prefixes.Trie is good for strings. I didn't solved this problem.I will solve after school's exams.

Bump, can admins fix this? -149 is not little deal.