C(6,3)-2*2-2=14. 本贴由[yinyin]最后编辑于:2006-12-17 19:1:34 |
不会那么多的。你的这一结果是仅基于"后排的小朋友比前排对应的小朋友高"的要求而没顾上"每排从左到右从低到高"的条件。 |
great. The method works for small numbers. Can we find a general method for any number? |
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