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# Python – Smallest integer possible from combination of list elements

• Last Updated : 29 Dec, 2019

Given a list of integers, the task is to get smallest integer possible from the combination of list elements. This is one of the problems that is essential in a competitive point of view and this article discusses various shorthands to solve this problem in Python. Let’s discuss certain ways in which this problem can be solved.

Method #1 : Using `sorted()` + lambda
The combination of the above function can be used to perform this task. The sorted function performs the sort of list indices converted into string and lambda functions handle the conversion and iteration operation.

 `# Python code to demonstrate ``# Smallest number from list``# using sorted() + lambda``import` `functools`` ` `# initializing list ``test_list ``=` `[``23``, ``65``, ``98``, ``3``, ``4``]`` ` `# printing original list``print` `(``"The original list is : "` `+` `str``(test_list))`` ` `# lambda for custom operation``custom ``=` `lambda` `i, j: ``-``1` `if` `str``(j) ``+` `str``(i) > ``str``(i) ``+` `str``(j) ``else` `1`` ` `# using sorted() + custom function``# Smallest number from list ``res ``=` `sorted``(test_list, key ``=` `functools.cmp_to_key(custom))`` ` ` ` `# printing result ``print` `(``"The smallest possible number : "` `+` `"".join(``map``(``str``, res)))`
Output :
```The original list is : [23, 65, 98, 3, 4]
The smallest possible number : 23346598
```

Method #2 : Using `itertools.permutation() + join() + min()`

The `itertools.permutation` can be used to get possible permutation and min function chooses the minimum of it after being converted to integer as a result of joined output as given by join function.

 `# Python3 code to demonstrate ``# Smallest number from list``# using itertools.permutation() + join() + min()``from` `itertools ``import` `permutations`` ` `# initializing list ``test_list ``=` `[``23``, ``65``, ``98``, ``3``, ``4``]`` ` `# printing original list``print` `(``"The original list is : "` `+` `str``(test_list))`` ` `# using itertools.permutation() + join() + min()``# Smallest number from list``res ``=` `int``(``min``((''.join(i) ``for` `i ``in` `permutations(``str``(i) ``                     ``for` `i ``in` `test_list)), key ``=` `int``))`` ` `# printing result ``print` `(``"The smallest possible number : "` `+` `str``(res))`
Output :
```The original list is : [23, 65, 98, 3, 4]
The smallest possible number : 23346598
```

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