In Python, what is the efficiency of the in keyword, such as in:
a = [1, 2, 3]
if 4 in a:
...
In Python, what is the efficiency of the in keyword, such as in: a
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In Python, what is the efficiency of the in keyword, such as in:
a = [1, 2, 3]
if 4 in a:
...
It depends on the right hand operand:
Classes can implement the special method
__contains__to override the default behavior (iterating over the sequence) and thus can provide a more (or less) efficient way to test membership than comparing every element of the container.Since you have a list in your example, it is iterated over and each element is compared until a match is found or the list is exhausted. The time complexity is usually
O(n).