⑴ python循环结构，range函数的使用
range()函数，作为Python的内置函数，用于生成一系列连续整数的列表，主要应用于for循环中，用作索引。函数有三种创建方式：first only parameter (create a list from 0 to stop - 1), second start & stop (create a list starting from start to stop - 1), third start, stop, step (create a list from start to stop, increment by step). Using 'in' and 'not in' with range() checks whether a specific integer is part of the integer sequence.
For loops include 'continue' and 'break' commands. 'continue' omits the remaining statements in the loop and moves to the next iteration, while 'break' terminates the loop immediately. 'else' blocks are executed upon normal loop termination, unless 'break' is encountered, then it skips the block.
With other iterable objects, range() is flexible. While loops, characterized by 'while condition:', proceed until the condition evaluates to false, allowing for single or block statements. 'continue' and 'break' in a while loop work similarly to their for loop counterparts.
'else' in a while loop executes the block of code if the loop ends naturally without encountering a 'break'. 'pass' serves as a placeholder, ensuring the code structure remains intact without executing any action.