Generate all subsequences and check which increasing ones are longest.
An array of length n has 2n subsequences. Checking each for increasing order is O(n).
Total: O(n⋅2n). Far too slow.
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The trap
Generate all subsequences and check which increasing ones are longest.
An array of length n has 2n subsequences. Checking each for increasing order is O(n).
Total: O(n⋅2n). Far too slow.