now there is such an array:
$a = [1,2,3,4,5];
I want to get the following result through some algorithm:
1,2
1,3
1,4
1,5
2,3
2,4
2,5
3,4
3,5
4,5
is a group of two or two, and there is also a possibility of a group of three
. How is that calculated?
do you know that there are great gods?
any number of combinations are supported, where 3 in the combine ($arr, 3) method represents a group of three.
these combinations remove combinations that have duplicate numbers.
this wave of operations is awesome
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