What is the syntax for array slicing?

Array slicing syntax: arr[start:end], where start is the starting index (inclusive) and end is the ending index (exclusive). Practical case: Taking the fruits array as an example, fruits[1:3] takes out the elements from index 1 to index 3 (excluding 3) and returns ['banana', 'cherry']. Other examples: fruits[0:2] takes the first two elements, fruits[2:] takes the elements at index 2 and after, fruits[:3] takes the first three elements, and fruits[-3:] takes the last three elements. It should be noted that slicing returns not a copy of the array but a reference to the original array. Negative indexes are counted from the end of the array.

Array slicing: syntax and practical cases

Grammar:

arr[start:end]

where :

• arr is the array to be sliced.
• start is the starting index of the slice (inclusive).
• end is the end index of the slice (exclusive).

Practical case:

Suppose we have an array of fruits:

fruits = ["apple", "banana", "cherry", "dog"]

Use slices to remove Specified range of fruits in the array:

# 从索引 1 开始到索引 3 结束（不包括索引 3）
sliced_fruits = fruits[1:3]

# 输出切片结果
print(sliced_fruits)

Output:

['banana', 'cherry']

Other examples:

• fruits[0:2]: Take out the first and second elements of the array.
• fruits[2:]: Take out the elements at index 2 and after in the array.
• fruits[:3]: Take out the first three elements in the array.
• fruits[-3:]: Take out the last three elements in the array.

Note:

• Slicing returns not a copy of the array, but a reference to the original array.
• If start or end exceeds the array bounds, slicing will return an empty list.
• You can also use negative indexes (counting from the end of the array).

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