If the invader chooses the hard pass he will lose one battalion of his army simply in getting over the mountains, simply in going through the hard pass.

如果侵略者选择崎岖的路,仅在穿越阿尔卑斯山的途中,他就要损失一个营的兵力,这就是选崎岖之路的代价

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So if you defend the easy pass, from his point of view, it doesn't matter whether he chooses the easy pass and gets one in there or the hard pass, he gets one in there.

那么如果你防守平坦的路,从他的立场出发,无论怎么选择,选崎岖之途收益是1,而选择平坦之途的收益也是1

耶鲁公开课 - 博弈论课程节选