soulmachine/leetcode — pull request #14 by x1957 (2014-01-14 02:30:44+00:00)
Title: Update chapTree.tex

Unique Binary SearchTrees 时间复杂度O(n^2)

for (int i = 2; i <= n; ++i) {
for (int k = 1; k <= i; ++k)
f[i] += f[k-1] * f[i - k];
}