An old professor at a university was in the habit of starting each days lecture with a vulgar joke. After one particularly egregious example, all the female studnts in the class held a meeting. They decided that the next time he spoke rudely would be the last, as they would leave the lecture hall, never to return.
The very next day, the professor walked into the hall, and began by asking,
Have you heard about the shortage of whores in India?
As one, en masse, the women in the hall rose, and began to file out.
At this point, the professor raised his hand, and cried out,
Wait, ladies! The boat doesnt leave until tomorrow!