檢視循环结构的原始碼

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|<center>'''循环结构'''<br><img
src=" https://gimg2.baidu.com/image_search/src=http%3A%2F%2Fimg2020.cnblogs.com%2Fblog%2F1360293%2F202011%2F1360293-20201124151240974-691700146.png&refer=http%3A%2F%2Fimg2020.cnblogs.com&app=2002&size=f9999,10000&q=a80&n=0&g=0n&fmt=auto?sec=1658451655&t=50ff1abf2e684643c9e334fb4dfa1c29" width="280"></center><small>  圖片來自百度</small> 
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'''循环结构'''是指在程序中需要反复执行某个功能而设置的一种程序结构。它由循环体中的条件，判断继续执行某个功能还是退出循环。根据判断条件,循环结构又可细分为以下两种形式:先判断后执行的循环结构和先执行后判断的循环结构。