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Generate Parentheses

Problem statement​

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

Example 1:

Input: n = 3Output: ["((()))","(()())","(())()","()(())","()()()"]

Example 2:

Input: n = 1Output: ["()"]

Constraints:

  • 1 <= n <= 8

My solution​

/**
 * @param {number} n
 * @return {string[]}
 */
var generateParenthesis = function(n) {
    const results = [];
    
    function parse(left, right, str) {
        if (left > right) {
            return;
        }
        
        if (left === 0 && right === 0) {
            results.push(str)
            return;
        }
        
        if (left > 0) {
            parse(left - 1, right, str + "(")
        }
        if (right > 0) {
            parse(left, right - 1, str + ")")
        }
    }
    
    parse(n, n, "");
    return results;
};