writeups/2020/rgbctf/insert-creative-algo-chall-.../challenge.txt

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Find the total number of unique combinations for input values of x = 4 and n = 12
There exists a set of values, r, with values binary increasing (2^0, 2^1, ... 2^(n-1))
A combination is a set of x values where each value is generated by creating x subsets of r with all values within a subset being summed
The x subsets should use all values in r exactly once.
Example Case:
Input:
x = 3
n = 5
Given the input above we can create a set r that consists of the following n values
[2^0, 2^1, 2^2, 2^3, 2^4]
OR
[1, 2, 4, 8, 16]
Each combination is formed via x subsets of the set [1, 2, 4, 8, 16]
[16], [2,8], [1, 4]
[1, 2, 4], [8], [16]
[1, 4], [2, 8], [16]
...
This renders sets of size x that are the sums of the elements of each set
16, 10, 5
7, 8, 16
5, 10, 16
...
Note: combination 1 and combination 3 are the duplicates and should not be counted twice as they both consist of 5, 10, and 16
All possible unique combinations for x = 3 and n = 5:
3 8 20
4 8 19
1 12 18
4 9 18
5 8 18
2 12 17
4 10 17
6 8 17
1 14 16
2 13 16
3 12 16
4 11 16
5 10 16
6 9 16
7 8 16
1 2 28
1 4 26
2 4 25
1 6 24
2 5 24
3 4 24
1 8 22
2 8 21
1 10 20
2 9 20
Final Output:
25
(There are 25 combinations generated above)
*IMPORTANT*
The answer should be formatted as rgbctf{[output value here]} with your output value replacing [output value here]