Is there any time complexity difference between recursive and iterative approach?

Short answer: no. Unless you optimize the algorithm using dynamic programming or such, there is no change to time complexity. There is also no change to space complexity, don't know where you got that idea.. However, in many programming languages there is an inherent overhead to using recursion, since they must store the stack as well, which uses more memory.

This can be slower, especially if it is not tail recursion.

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