@@ -0,0 +1,510 @@
+public class Solution %7B%0A    HashMap%3CInteger, Integer%3E hm  = new HashMap%3CInteger, Integer%3E();%0A    public int numTrees(int n) %7B%0A        for(int i = 0; i %3C n+1; i ++)%7B%0A            setHashMap(i);%0A        %7D%0A        return hm.get(n);%0A    %7D%0A    %0A    public void setHashMap(int n)%7B%0A        if(n == 0)%7B%0A            hm.put(0, 1);%0A        %7Delse%7B%0A            int tmp = 0;%0A            for(int i = 0; i %3C n; i ++)%7B%0A                tmp += hm.get(i) * hm.get(n-1-i);%0A            %7D%0A            hm.put(n, tmp);%0A        %7D%0A    %7D%0A%7D

Q96 Unique Binary Search Trees