Given a set of candidate numbers (candidates) (without duplicates) and a target number (target), find all unique combinations in candidates where the candidate numbers sums to target.
The same repeated number may be chosen from candidates unlimited number of times.
Note:
All numbers (including target) will be positive integers.
The solution set must not contain duplicate combinations.
Example 1:
Input: candidates = [2,3,6,7], target = 7,
A solution set is:
[
[7]
[2,2,3]
]
Example 2:
Input: candidates = [2,3,5], target = 8,
A solution set is:
[
[2,2,2,2]
[2,3,3],
[3,5]
]
Given these problem, i need help on:
1) What should be my approach to solve these type of questions.
2) In which direction should i think or on what basis should i start to think for solving these questions.
Thanks in advance.
PS:i don't need the solution, but i can't think of any starting point.
What I have tried:
i tried linear way of thinking, but it is not sufficient.