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 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
• Description: As long as the conditions If true, the loop body will always be executed.

range() function

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

Example:

# 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)

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 thebreakstatement within the loop body to exit the loop.
• Use thecontinuestatement in the loop body to skip the current iteration and continue with the next iteration.

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