用栈来完成遇到左括号就压入对应的右括号遇到右括号就比较栈顶元素一致则弹出class Solution { public boolean isValid(String s) { StackCharacter s0 new Stack(); char[] ch s.toCharArray(); for(int i 0;i ch.length;i){ if(s0.isEmpty() (ch[i] ) || (ch[i] ] || ch[i] }))){ return false; } if(ch[i] (){ s0.push()); }else if(ch[i] [){ s0.push(]); }else if(ch[i] {){ s0.push(}); }else if(ch[i] s0.peek()){ s0.pop(); }else{ return false; } } return s0.isEmpty(); } }