How are the coin change change problem and Ways to sum to N using array elements with repetition allowed giving different answers based on ordering of elements in the subset.

Both of the questions are one and the same except for a slightly different way of framing the problem. Which test case ended up giving different answers?

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in the coin change order of coins does not matter while in summation problem order does matter.

eg for arr={1,2,3} and k=3

coin change output = 3

summation output = 4

Don’t you have your answer right there? If the order doesn’t matter {1, 1, 2} and {1, 2, 1} and {2, 1, 1} are counted as 1. If the order matters there are counted as 3. What is your doubt?

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I am confused how is interchanging the loops giving results based on order.