# Range Sum Query 2d – Mutable [Solved]

## Understanding Range Sum Query 2D – Mutable

When it comes to efficiently performing range sum queries in a 2D matrix, the Range Sum Query 2D – Mutable data structure is an essential tool. This powerful data structure allows us to quickly compute the sum of elements within a given rectangular area of the matrix.

### The Basics of Range Sum Query 2D – Mutable

At its core, the Range Sum Query 2D – Mutable data structure is based on the concept of segment trees. Segment trees are binary trees that divide the input array into segments, with each node in the tree representing a segment of the array.

By precomputing sums for each segment of the array, the Range Sum Query 2D – Mutable data structure allows us to efficiently calculate the sum of elements within any given rectangular area of the matrix. This makes it a valuable tool for a wide range of applications, including image processing, computer graphics, and more.

### How Range Sum Query 2D – Mutable Works

When performing a range sum query on a 2D matrix using the Range Sum Query 2D – Mutable data structure, we start by constructing a segment tree that represents the rows of the matrix. Each node in the tree stores the sum of elements in the corresponding row segment.

Once the segment tree is constructed, we can efficiently calculate the sum of elements within a rectangular area by traversing the tree and summing the values stored in the nodes that correspond to the rows within the given range. This process allows us to compute the range sum query in O(log n) time complexity, making it a highly efficient solution for large matrices.

#### Optimizing Range Sum Query 2D – Mutable

To further optimize the performance of the Range Sum Query 2D – Mutable data structure, we can implement lazy propagation techniques. Lazy propagation allows us to delay the updates to the segment tree until they are absolutely necessary, reducing the overall number of updates and improving the efficiency of the data structure.

By carefully managing the updates to the segment tree using lazy propagation, we can ensure that the Range Sum Query 2D – Mutable data structure performs optimally even for large matrices with frequent range sum queries.

### Conclusion

In conclusion, the Range Sum Query 2D – Mutable data structure is a powerful tool for efficiently computing range sum queries in a 2D matrix. By leveraging the concept of segment trees and implementing lazy propagation techniques, we can achieve fast and efficient computation of range sums even for large matrices. This makes the Range Sum Query 2D – Mutable data structure a valuable asset for a wide range of applications where fast and accurate computation of range sums is essential.