# How to get all combination of n binary value? [duplicate]

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### Question :

How to get all combination of n binary value? [duplicate]

In Python, how can I get all combinations of `n` binary values `0` and `1`?

For example, if `n = 3`, I want to have

``````[ [0,0,0], [0,0,1], [0,1,0], [0,1,1], ... [1,1,1] ]  #total 2^3 combinations
``````

How can I do this?

``````import itertools
lst = list(itertools.product([0, 1], repeat=3))
``````

This will yield a list of tuples (see here)

You can easily change this to use a variable `repeat`:

``````n = 3
lst = list(itertools.product([0, 1], repeat=n))
``````

If you need a list of lists, then you can use the `map` function (thanks @Aesthete).

``````lst = map(list, itertools.product([0, 1], repeat=n))
``````

Or in Python 3:

``````lst = list(map(list, itertools.product([0, 1], repeat=n)))
# OR
lst = [list(i) for i in itertools.product([0, 1], repeat=n)]
``````

Note that using `map` or a list comprehension means you don’t need to convert the product into a list, as it will iterate through the `itertools.product` object and produce a list.

Without using any in-build functions or smart techniques we can get like this.

``````def per(n):
for i in range(1<<n):
s=bin(i)[2:]
s='0'*(n-len(s))+s
print (map(int,list(s)))
per(3)
``````

output

``````[0, 0, 0]
[0, 0, 1]
[0, 1, 0]
[0, 1, 1]
[1, 0, 0]
[1, 0, 1]
[1, 1, 0]
[1, 1, 1]
``````

``````bin = [0,1]