以下叙述中错误的是______。
A．可以通过typedef增加新的类型
B．可以用typedef将已存在的类型用一个新的名字来代表
C．用typedef定义新的类型名后，原有类型名仍有效
D．用typedef可以为各种类型起别名，但不能为变量起别名
参考答案：A
解析： 关键字typedef的作用只是将C语言中的已有的数据类型作了置换，并不是增加新的类型，所以A错误。
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pedestrian has as many rules to 2_____ as the driver of car. You should walk at the sidewalk or at the 3_____ of the road. Always look carefully before you walk across the street? If you ride a bike, don't ride in the middle of the road or run 4_____ red traffic lights. When you ride a bike with a friend, don't look around to talk. If you drive, you should 5_____ at the traffic lights. You must always 6_____ a seat belt (安全带). Without belts 7_____ the driver and the passengers may be badly hurt in a sudden accident. Someone may be thrown out through the window? You may not need to drive a bus, but 8_____ if you have to travel in one. Get in or get off a bus only when it has come to a 9_____. When it is full, don't try to get inside 10_____ you may fall off. |