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 .