【Leetcode-1021】删除最外面的括号

package com.leetcode;

/**
 * L-1021
 * @author raymond
 *
 */
public class RemoveOuterParentheses {
    
    public static void main(String[] args) {
        
        String s1 = "(()())(())(()(()))";
        String result1 = removeOuterParentheses(s1);
        System.out.println(result1);
        
        /*String s2 = "()()";
        String result2 = removeOuterParentheses(s2);
        System.out.println(result2);
        
        String s3 = "(()())(())";
        String result3 = removeOuterParentheses(s3);
        System.out.println(result3);*/
        
    }
    
    /**
     * 思路：
     * @param S
     * @return
     */
    public static String removeOuterParentheses(String S) {
        char[] inArr = S.toCharArray(); // "(()())(())(()(()))" 字符串转字符数组
        char[] resultArr = new char[inArr.length];
        int bracesCnt = 0;
        int outIncr = 0; 
        for (int i = 0; i < inArr.length ; i++) {
            if (inArr[i] == ')') {
                bracesCnt--; //每遍历至最外面一个')', bracesCnt都会减至0, 然后从最后面一个'(', bracesCnt重新开始自增
                if(bracesCnt != 0){
                    resultArr[outIncr++] = ')';
                }
            } else {
                if (bracesCnt != 0) {
                    resultArr[outIncr++] = '(';
                }
                bracesCnt++; //第一个'('不存入resultArr数组
            }
            //System.out.println(bracesCnt + "------" + outIncr);
        }
        return new String(resultArr).substring(0, outIncr);
    }
}