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Calculate the length of a sequence or set using Python's len() function
Calculate the length of a sequence or set using Python's len() function

Use Python's len() function to calculate the length of a sequence or set
In Python, the len() function is a very useful function that can be used Calculate the length of a sequence or set. Whether it's a string, list, tuple, or collection, the len() function can quickly and accurately tell you their length.
Let’s look at some specific examples to demonstrate the use of the len() function.
- Calculate the length of a string
String is the most common sequence type. Through the len() function, we can easily get the length of the string.
str = "Hello World" print(len(str)) # 输出结果:11
- Calculate the length of a list
List is one of the most commonly used data structures in Python. Through the len() function, we can get the number of elements in the list .
list = [1, 2, 3, 4, 5] print(len(list)) # 输出结果:5
- Calculate the length of a tuple
Tuples are similar to lists and are also a data structure used to store multiple elements. Through the len() function, we can get the number of elements in the tuple.
tuple = (1, 2, 3, 4, 5) print(len(tuple)) # 输出结果:5
- Calculate the length of a set
A set is an unordered and non-repeating data structure. Through the len() function, we can quickly get the number of elements in the collection.
set = {1, 2, 3, 4, 5}
print(len(set)) # 输出结果:5- Calculate the length of the dictionary
The dictionary is a data structure used to store key-value pairs in Python. Through the len() function, we can count the number of key-value pairs in the dictionary.
dictionary = {'a': 1, 'b': 2, 'c': 3}
print(len(dictionary)) # 输出结果:3It should be noted that the length of the dictionary refers to the number of key-value pairs in the dictionary, not the number of all elements in the dictionary.
Summary:
The len() function is a simple and powerful built-in function through which we can quickly obtain the length of a sequence or set. Whether it is a string, list, tuple, set or dictionary, the len() function is applicable. Mastering the use of the len() function can process data more conveniently and optimize the running efficiency of the program.
Hope the above examples can help you better understand and use the len() function. come on!
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