LeetCode - The Two Pointers Part

There are two types of two pointers.

• for only one items

If we only care about the start and the end in an array, we can use two pointers.

1. Container With Most Water

2. Trapping Rain Water

If we need to find kth node from the end, we can use two pointers.

1. Remove Nth Node From End of List

• both from start but for different items

1. Merge Two Sorted Lists

2. Like indexOf in String Implement strStr()

3. Merge Sorted Array

Another type is for insert index, when we want to remove some element in array in place, we can use an insert index to indicate the insert position and another pointer to do the iteration.

1. Remove Duplicates from Sorted Array

2. Remove Element