标签：uniq == arc The nts any col struct tor
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
Constraints:
1 <= n <= 19class Solution { public: int numTrees(int n) { vector<int> dp(n+1,0); int res; if(n == 1) return 1; if(n == 2 )return 2; dp[0] = 1; dp[1] = 1; dp[2] = 2; for(int i=3;i<=n;i++){ for(int j=1;j<=i;j++) { dp[i] += dp[j-1]*dp[i-j]; } } return dp[n]; } };
96. Unique Binary Search Trees(dp)
标签：uniq == arc The nts any col struct tor
原文地址：https://www.cnblogs.com/wsw-seu/p/14258373.html
