The Falling Leaves UVA - 699 Each year, fall in the North Central region is accompanied by the brilliant colors of the leaves on the trees, followed quickly by the falling leaves accumulating under the trees. If the same thing happened to binary trees,
Each year, fall in the North Central region is accompanied by the brilliant colors of the leaves on the trees, followed quickly by the falling leaves accumulating under the trees. If the same thing happened to binary trees, how large would the piles of le
分析： 0. 统计每列的所有结点权值之和的一个惯性思维下的解决方案：从左至右依次找到每列所有结点，求其和。显然不现实。 正确的办法(貌似就是桶方法的思想)：开辟一个sum数组，遍历一遍整棵树，在整条遍历路径中的走到的每个结点，都可以知道其所列号idx，直接sum[idx] += val。这样，遍历
