Understanding the two pointer pattern

To perform any operation on the data items of an array, we either need to know their index in advance or traverse the array using loops. An array is generally only traversed in one direction at a time, either from the start to the end or the other way around, depending on the problem we are trying to solve. However, some problems require traversing the array in both directions simultaneously, and we often resort to nested loops for such cases, which are inefficient.

For some of these problems, we can use the two-pointer traversal technique to traverse an array simultaneously from both ends. This enables us to solve such problems in linear time and a single pass, which would otherwise require inefficient nested loops.

In this course, we will learn more about the two-pointer technique and how to identify a problem as a two-pointer pattern problem.