Master this problem using the Backtracking pattern.
When approaching Combination Sum, look for key problem signals that suggest using the Backtracking pattern. Focus on reducing redundant iterations, maintaining state invariant, and optimizing space-time complexity.
Key Invariant
Maintain optimal range bounds or hash frequency state during traversal.
Expected Complexity
Time: O(N) or O(N log N) | Space: O(1) to O(N)
Study Resource
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