Spoj INCSEQ
How can we solve spoj problem INCSEQ using segment tree?
Here is the link to the problem
http://www.spoj.com/problems/INCSEQ/
I think, that you can solve this task in such way :
You will use K segment trees.
1. Sort all elements of given array in non-decreasing order.
About sort : if elements are equal — the minimal element will be element which has the rightmost position.
2. You should update every segment tree in such way :
sum = getSumOnPositionInPrevSegTree(1, myElementPosition - 1)
3. Le'ts add the value of sum in the current segment tree in position myElementPosition.
My AC code here
If I want to find distinct increasing subsequence as in this question http://www.spoj.com/problems/INCDSEQ/
what modification I need to make in the above code?
Another ways to solve the problem:
Can you please explain how BIT is working for this problem? Also , why we need to increment a[i] during scanning the input
Increment is because BIT is 1-based structure. Bit-based solution is simply in k turns calculate on each turn number of sequences of length i ending in pos.
I think, that you can solve this task in such way :
You will use K segment trees.
1. Sort all elements of given array in non-decreasing order.
About sort : if elements are equal — the minimal element will be element which has the rightmost position.
2. You should update every segment tree in such way :
3. Le'ts add the value of sum in the current segment tree in position myElementPosition.
My AC code here
If I want to find distinct increasing subsequence as in this question http://www.spoj.com/problems/INCDSEQ/
what modification I need to make in the above code?
Another ways to solve the problem:
Can you please explain how BIT is working for this problem? Also , why we need to increment a[i] during scanning the input
Increment is because BIT is 1-based structure. Bit-based solution is simply in k turns calculate on each turn number of sequences of length i ending in pos.