# LeetCode Reverse Integer: Overflow Detection

The key to this LeetCode Reverse Integer problem is the overflow detection, the algorithm is simple and you do not have to keep each single digits.

# LeetCode Remove Element: Swap with Two Pointers

LeetCode Remove Element: Linear scan the array, swap the element of the given value with the last one in the array that are maintained by two pointers.

# LeetCode Remove Duplicates from Sorted Array I and II: O(N) Time and O(1) Space

LeetCode Remove Duplicates from Sorted Array I and II can be solved in O(N) Time, O(1) Space by using two pointers to remove duplicates on the fly while scanning.

# LeetCode Plus One: Math Array Simulation

LeetCode Plus One: Math Simulation of plus one by array, just simulate the process of adding one and handle both sum and carry carefully.

# LeetCode Permutations I and II: DFS, Swap and Sorting

3 methods including DFS, Iterative Swap, Recursive Swap are given (pros and cons) to solve LeetCode Permutations problem and use sorting to remove duplicates.