leetcode:有效括號java
阿新 • • 發佈:2018-12-20
class Solution { public boolean isValid(String s) { HashMap<Character,Character> juge = new HashMap(); juge.put(')', '('); juge.put('}', '{'); juge.put(']', '['); Stack<Character> res = new Stack(); for (int i = 0; i < s.length(); i++) { char k = s.charAt(i); if (juge.containsKey(k)) { if (res.isEmpty()) { return false; } else { char m = res.pop(); if (m != juge.get(k)) { return false; } } } else { res.push(s.charAt(i)); } } return res.empty(); } }