In the Subset Sum problem can some of the given numbers $a_1,a_2,a_3,\dots,a_n$ be the same? For example, we might have $[1,1,1,2,3,4]$ and the target is $5$? Can I assume that I have a specific solution with numbers $2$ and $3$ and $1,1,1$ and $2$ is not?
Does Subset Sum allow multisets?
complexity theory;terminology