How to write loop

Loop statements are used to repeatedly execute a piece of code. The syntax is as follows: for loop: used to iterate each element in a sequence or range. while loop: used to repeatedly execute code while a condition is true. do-while loop: Similar to a while loop, but the code is executed first and then the condition is checked.

Writing of loops

The loop statement is a statement that controls the program flow in programming, which allows code blocks Repeat a specified number of times or until a specific condition is met. In Python, you can use the following three types of loops:

for loop

• Usage: for <variable> in < Iterable object>
• Description: Traverse each element in an iterable object (such as a list, tuple, dictionary) and assign each element to a variable.

while loop

• Usage: while <Conditions>
• Description: As long as the conditions If true, the loop body will always be executed.

range() function

• Usage: for <variable> in range(<start>, < end>, <step>)
• Description: Generate a range of numbers from the start value to the end value (excluding the end value), increasing by step size.

Example:

<code class="python"># for 循环
for item in [1, 2, 3, 4, 5]:
    print(item)

# while 循环
count = 0
while count < 5:
    print(count)
    count += 1

# range() 函数
for number in range(1, 10, 2):
    print(number)</code>

Note:

• Make sure that the loop condition will eventually be false, Otherwise it will fall into an infinite loop.
• Use an appropriate step size to traverse the range to avoid skipping elements.
• Use the break statement within the loop body to exit the loop.
• Use the continue statement in the loop body to skip the current iteration and continue with the next iteration.

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