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Number of ways to make coin change when change is larger (repetitions of coins are allowed and order does matter)

Revision en2, by naveen_1729, 2021-05-09 10:08:48

Hi Fellow Coders,

Hope you are all doing good. This is my first blog. Today I gave Hackwithinfy test. I got asked a question similar to the standard DP problem which is Count the number of ways to make the change (repetitions of coins are allowed and order does matter). I know this problem can be solved in Quadratic time

O(N * W)

W — > Required Change

N — > Number of coins

But the constraints given in the problem are huge

1 <= N <= 10^5

1 <= W <= 10^9

1 <= A[i] <= 10^2 (A[i] — > stores the value of the coin)

I was so sure this would give me a TLE. But, I couldn't come up with a better approach than the standard one. I wonder if there is a better approach that would have given me an AC.

#### History

Revisions

Rev. Lang. By When Δ Comment
en4 naveen_1729 2021-05-09 10:11:33 102 Tiny change: 'atic time O(N * W) \nW &mdash' -> 'atic time \n\nO(N * W) \n\nW &mdash' (published)
en3 naveen_1729 2021-05-09 10:11:09 102 Reverted to en1
en2 naveen_1729 2021-05-09 10:08:48 102 Tiny change: 'atic time O(N * W) \nW &mdash' -> 'atic time \n\nO(N * W) \n\nW &mdash'
en1 naveen_1729 2021-05-09 09:58:11 786 Initial revision (saved to drafts)