Given n pairs of parentheses, write a function to generate all combinations of well-formed parentheses.
For example, given n = 3, a solution set is:
[
"((()))",
"(()())",
"(())()",
"()(())",
"()()()"
]
public List<String> generateParenthesis(int n) {
List<String> aryList = new ArrayList<String>();
getString(aryList, "", 0, 0, n);
return aryList;
}
private void getString(List<String> list,String str,int open,int close,int max) {
if (str.length()==2*max) {
list.add(str);
return;
}
if (open<max) {
getString(list, str+"(", open+1, close, max);
}
if (close<open) {
getString(list, str+")", open, close+1, max);
}
}
