22. Generate Parentheses
Given n pairs of parentheses, write a function to generate all combinations of well-formed parentheses.
c++代码：
//
// main22.cpp
// LeetCode
//
// Created by linSir on 2017/9/6.
// Copyright © 2017年 58qifu. All rights reserved.
//
#include <stdio.h>
#include <string>
#include <vector>
#include <iostream>
class Solution {
public:
std::vector<std::string> generateParenthesis(int n) {
std::vector<std::string> allComb;
std::string comb;
findParenthesis(n, 0, 0, comb, allComb);
return allComb;
}
void findParenthesis(int n, int nleft, int nright, std::string &comb, std::vector<std::string> &allComb) {
if(nleft==n && nright==n) {
allComb.push_back(comb);
return;
}
if(nleft<n) {
comb.push_back('(');
findParenthesis(n, nleft+1, nright, comb, allComb);
comb.pop_back();
}
if(nright<nleft) {
comb.push_back(')');
findParenthesis(n, nleft, nright+1, comb, allComb);
comb.pop_back();
}
}
};
int main22(){
std::cout << "static constructor\n";
return 0;
}
