What is the method to utilize fenwick tree for solving this problem?

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The problem statement was not provided. However, Fenwick Tree, also known as Binary Indexed Tree, is useful for solving problems related to range query and single point update. The basic idea behind Fenwick Tree is to represent an array in a tree structure to improve the time complexity of updating and querying a range of values. The methods commonly used to implement a Fenwick Tree are:

1. Construction: A Fenwick Tree can be constructed from an input array in O(nlogn) time using the following steps:

   • Initialize an empty Fenwick Tree of size n+1.
   • Iterate over each element in the input array and update the corresponding positions in the Fenwick Tree by adding the value of the element to the position and its parent nodes.

2. Query: A query can be performed on a Fenwick Tree to get the sum of a range of values in O(logn) time using the following steps:

   • Calculate the sum of all nodes from the root of the tree to the right endpoint of the range.
   • Calculate the sum of all nodes from the root of the tree to the left endpoint of the range minus one.
   • Subtract the second sum from the first sum to obtain the range sum.

3. Update: An update can be performed on a Fenwick Tree to change the value of an element in O(logn) time using the following steps:

   • Traverse the tree from the leaf node corresponding to the element to the root node, updating the value of each node by adding the difference between the new value and the old value of the element.

These methods can be used to solve various problems related to range sum queries, range minimum/maximum queries, and more.