I looked carefully at the submissions. These are literally the same implementation if you remove all of the unnecessary variables being defined. There are hundreds of (fake) users with that same implementation.

The example for n=65536, k=65535 would be (65535, 65534), (0, 1), (2, 65532), (3, 65533). The rest are just paired so that their sum is 65535.

It was "n 0".

EDIT: I guess it was "n 0" "n n-1".

I don't know much C++, but the most common mistake that I know of is forgetting that after you perform the operation, elements right after the ones you just changed might already be equal to the target. Checking this condition requires a while loop.

If every subarray needs to have strictly more in range than out of range, then the entire array needs to have at least k more in range than out of range. Finding the range requires constructing a copy of the array and then sorting, and then minimizing arr[i+dist]-arr[i]. Constructing is then a linear scan waiting for the moment in range > out of range, except for the last one being the rest of the array.

((SUM(i=0 to m-1) (m-i)*(n choose i))/2^(n-1))*k

2E ended up being a logic puzzle instead of a coding problem. Once you solve the logic puzzle, the implementation becomes O(n^2).

The test case you included is not incorrect. The incorrect test case occurs at test case 11, or n=13. After the first 9 steps, the array has become all 1's except [1,2,3,13] at indices 1,2,3,13. After step 10, the array is [1,2,3,5]. After step 11, the array is [1,2,1,5]. After step 12, the array is [1,2,1,3]. We still need 2 more steps to get the desired array, yet your response only has room for 1 more step.

For problem D, did anyone else take just the indices n and ceil(n^((sqrt(5)-1)/2))? It works but there are a few corner cases. Head bashing that I didn't get the direct square root solution.

This assumes that the repeat number is necessarily the smallest number, which is not necessarily the case.

If it can, then I think it will be only as a by-product of the closed form solution.