During the Russian occupation of Czechoslovakia, a citizen of Prague meets a good fairy in the woods.

"Well" says the Good Fairy, "you are entitled to three wishes. Think carefully for you have only one opportunity like this in a life time."

The man thinks for a while.

"For my first wish I would like the Chinese Red Army to march into Prague on a Monday morning, and to go home on the Tuesday night."

"For my second wish I would like the Chinese Red Army to march into Prague on a Wednesday morning, and to go home on the Thursday night.

"And for my last wish I would like the Chinese Red Army to march into Prague on a Friday morning, and to go home on the Saturday night."

"Well, I can do that", said the Good Fairy. "But why?"

"Imagine what it will do to the Russians to have the Chinese Army march over them six times in a week!"