# I am confused by a condition of this question. someone explain it please.

• Question says

Given a collection of candidate numbers (C) and a target number (T), find all unique combinations in C where the candidate numbers sums to T.

Each number in C may only be used once in the combination.

For example, given candidate set [10, 1, 2, 7, 6, 1, 5] and target 8,
A solution set is:

[
[1, 7],
[1, 2, 5],
[2, 6],
[1, 1, 6]
]

i am confused of this condition
Each number in C may only be used once in the combination.
as in this example it has the combination [1,1,6] i.e. repeating 1's

it is highly appreciable if somebody explains it. Thank you .

• i found the same problem ,but after reading carefully and analyzing the conditions you will found that it is not a problem. Try again yourself before asking here.

• The example [1, 1, 6], there is no duplicate number in the combination, because there are two 1 in C.

The purpose is that you are not supposed to give a [1, 1, 1, 1, 1, 1, 1, 1] as solution.

• C is a collection, not a set, so C can have a bunch of duplicates in it. You can use any number at a specific index twice. So you can use both C[0] = 5 and C[3] = 5, but not C[1] = 1 more than once.

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