Leetcode 22 Generate Parentheses Solution in java | Hindi Coding Community

 

Given n pairs of parentheses, write a function to generate all combinations of well-formed parentheses.

Example 1:

Input: n = 3

Output: ["((()))","(()())","(())()","()(())","()()()"]

Example 2:

Input: n = 1

Output: ["()"]

 

class Solution {

public List<String> generateParenthesis(int n) {

List<String> res = new ArrayList<String>();

recurse(res, 0, 0, "", n);

return res;

}

public void recurse(List<String> res, int left, int right, String s, int n) {

if (s.length() == n * 2) {

res.add(s);

return;

}

if (left < n) {

recurse(res, left + 1, right, s + "(", n);

}

if (right < left) {

recurse(res, left, right + 1, s + ")", n);

}

}

}