Why are the initial values ​​in Python loops skipped?

Python loop skips parsing of initial values

In Python loops, sometimes the initial value is skipped, which is usually related to loop conditions and statements inside the loop body (such as continue ). The following code is used as an example to analyze the reason why the initial value is skipped:

 i = 10
while i <p> <strong>Question:</strong> Why does the output result contain <code>i = 10</code> ?</p><p> <strong>Cause:</strong> The condition of <code>while</code> loop in the code is <code>i  . At the beginning of each iteration, the program first executes <code>i = 1</code> , increasing the value of <code>i</code> by 1. This means that when the initial value of <code>i</code> is 10, the program first changes it to 11 and then determines whether <code>11 % 5</code> is equal to 0. Since it is not equal to 0, the <code>continue</code> statement is executed, skip <code>print(i)</code> statement and enter the next loop. This process is repeated until the value of <code>i</code> becomes 15 (15 % 5 == 0), and <code>print(i)</code> statement is executed and 15 is printed. Therefore, after the initial value 10 is modified by <code>i = 1</code> statement, it is no longer the start value of the loop before the conditional judgment, resulting in it not being printed.</code></p><p> In short, since <code>i = 1</code> statement is executed before the conditional judgment, the initial value is modified in the first iteration, and due to the skip effect of the <code>continue</code> statement, the initial value is not printed out in the end. To avoid this, it is necessary to adjust the code logic, such as placing the <code>i = 1</code> statement after the conditional judgment, or modifying the loop conditions and internal logic.</p>

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