96.unique-binary-search-trees.cpp

/*
 * @lc app=leetcode id=96 lang=cpp
 *
 * [96] Unique Binary Search Trees
 *
 * https://leetcode.com/problems/unique-binary-search-trees/description/
 *
 * algorithms
 * Medium (45.16%)
 * Total Accepted:    186.2K
 * Total Submissions: 412.2K
 * Testcase Example:  '3'
 *
 * Given n, how many structurally unique BST's (binary search trees) that store
 * values 1 ... n?
 *
 * Example:
 *
 *
 * Input: 3
 * Output: 5
 * Explanation:
 * Given n = 3, there are a total of 5 unique BST's:
 *
 * ⁠  1         3     3      2      1
 * ⁠   \       /     /      / \      \
 * ⁠    3     2     1      1   3      2
 * ⁠   /     /       \                 \
 * ⁠  2     1         2                 3
 *
 *
 */
class Solution
{
  public:
    int numTrees(int n)
    {
        if (n <= 2)
            return n;
        int sum = 0;
        for (int i = 0; i < n; i++)
        {
        }
    }
};