Pat will walk from intersection X to intersection Y along a route that is confined to the square grid of four streets and three avenues shown in the map above. How many routes from X to Y can Pat take that have the minimum possible length?
Six
Eight
Ten
Fourteen
Sixteen
一共是五步,必须是三步向上,两步向右,至于怎么分配,随机, c 52 或者c53 。
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