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Python: Difference between revisions
→Dictionaries
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===Dictionaries=== | ===Dictionaries=== | ||
Dictionaries are hashmaps in Python | Dictionaries are hashmaps in Python<br> | ||
<syntaxhighlight lang="python"> | <syntaxhighlight lang="python"> | ||
# Create a dictionary | # Create a dictionary | ||
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# Or | # Or | ||
my_map = {1: "a", 2: "b"} | my_map = {1: "a", 2: "b"} | ||
# Check if a key is in a dictionary | |||
# O(1) | |||
d = {'1': 'one', '3': 'three', '2': 'two', '5': 'five', '4': 'four'} | |||
"1" in d | |||
# Check if a value is in a dictionary | |||
# Usually you should have a second dictionary if you need this functionality | |||
# O(n) | |||
'one' in d.values() | |||
</syntaxhighlight> | </syntaxhighlight> | ||