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GenerateParentheses.java
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51 lines (45 loc) · 1.33 KB
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//数字 n 代表生成括号的对数，请你设计一个函数，用于能够生成所有可能的并且 有效的 括号组合。
//
//
//
// 示例：
//
// 输入：n = 3
//输出：[
// "((()))",
// "(()())",
// "(())()",
// "()(())",
// "()()()"
// ]
//
// Related Topics 字符串 回溯算法
// 👍 1330 👎 0
package leetcode.editor.cn;
import java.util.ArrayList;
import java.util.List;
/**
* [22]括号生成
*/
public class GenerateParentheses {
//leetcode submit region begin(Prohibit modification and deletion)
class Solution {
public List<String> generateParenthesis(int n) {
List<String> result = new ArrayList<>();
helper(0, 0, n, result, "");
return result;
}
private void helper(int left, int right, int count, List<String> result, String s) {
if(left + right == count * 2) {
result.add(s);
return;
}
if(left < count) helper(left + 1, right, count, result, s + "(");
if(right < left) helper(left, right + 1, count, result, s + ")");
}
}
//leetcode submit region end(Prohibit modification and deletion)
public static void main(String[] args) {
Solution solution = new GenerateParentheses().new Solution();
}
}