比如串：(())()(())
(()(())())
((()))
(())()(())()
也就是用正则表达式表示所有合法的括号串？
------解决方案--------------------
用常规的吧，感觉用正则有点难。
String s="(())()(())()";
- Java code
public boolean checkValid(String s){int count=0;int index=0;while(count>=0){if(s.charAt(index)=='('){count++;}else if(s.charAt(index)==')'){}index++;if(index==s.length()-1){break;}}if(count!=0){System.out.println("不合法的");return false;}return true;}
------解决方案--------------------
- Java code
public class Test { public static void main(String[] args) { String s="(())()(())()"; checkValid(s); } public static boolean checkValid(String s) { int count = 0; int index = 0; while (count >= 0){ if (s.charAt(index) == '(') { count++; } else if (s.charAt(index) == ')') { count--; } index++; if (index==(s.length())) { break; } } if (count != 0) { System.out.println("不合法的"); return false; } System.out.println("合法的"); return true; }}
------解决方案--------------------
- Java code
String input = "(())()(())"; String input2; boolean validate = false; while(true) { input2 = input.replaceAll("([(][)])*", ""); if(input2.length() == input.length()) { break; } input = input2; } if(input.trim().equals("")) validate = true;