# Backtracking

## Combination Sum Problem

Problem: Given a collection of candidate numbers (C) and a target number (T), find all unique combinations in C where the candidate numbers sums to T. Each number in C may only be used once in the combination. Note: All numbers (including target) will be positive integers. Elements in a combination (a1, a2,…, ak) must Read More →

## N Queens – Backtracking Problem 2

BackTracking: Find a solution by trying one of several choices. If the choice proves incorrect, computation backtracks or restarts at the point of choice and tries another choice. It is often convenient to maintain choice points. In an exhaustive search algorithm you search every possible choice to reach to the goal state, however, the backtracking Read More →

## Finding All the Subsets of a Set – Backtracking Problem

Given a set of distinct integers, S, return all possible subsets. Note: Elements in a subset must be in non-descending order. The solution set must not contain duplicate subsets. For example, If S = [1,2,3], a solution is: [ [3], [1], [2], [1,2,3], [1,3], [2,3], [1,2], [] ] We use the backtracking method to solve Read More →