这题怎么做啊，只学到了循环结构[face]monkey2:018.png[/face][face]m

这题怎么做啊，只学到了循环结构[face]monkey2:018.png[/face][face]monkey2:018.png[/face][face]monkey2:018.png[/face][face]monkey2:018.png[/face]