Real-world problems

Many problems in the real world use the two pointers pattern. Let’s look at an example.

• Memory management: The two pointers pattern is vital in memory allocation and deallocation. The memory pool is initialized with two pointers: the start pointer, pointing to the beginning of the available memory block, and the end pointer, indicating the end of the block. When a process or data structure requests memory allocation, the start pointer is moved forward, designating a new memory block for allocation. Conversely, when memory is released (deallocated), the start pointer is shifted backward, marking the deallocated memory as available for future allocations. The end pointer remains fixed, acting as a safeguard against errors like overlapping allocations.

Does your problem match this pattern?

Yes, if all of these conditions are fulfilled:

• Linear data structure: The input data can be traversed in a linear fashion, such as an array, linked list, or string.
• Process pairs: Process data elements at two different positions simultaneously.
• Dynamic pointer movement: Both pointers move independently of each other according to certain conditions or criteria. In addition, both pointers might move along the same or two different data structures.