[Leetcode] Valid Parentheses (Java)

Given a string containing just the characters

'('

,

')'

,

'{'

,

'}'

,

'['

and

']'

,
determine if the input string is valid.

The brackets must close in the correct order,

"()"

and

"()[]{}"

are
all valid but

"(]"

and

"([)]"

are
not.

括号匹配，没考虑//,/* */," "等

import java.util.Stack;

public class ValidParentheses {
public boolean isValid(String s) {
Stack<Character> stack = new Stack<Character>();
for(int i=0;i<s.length();i++){
char c = s.charAt(i);
if(c=='('||c=='[')
stack.add(c);
else if(c==')'){
if(!stack.isEmpty()&&stack.peek()=='(')
stack.pop();
else
return false;
}else if(c==']'){
if(!stack.isEmpty()&&stack.peek()=='[')
stack.pop();
else
return false;
}
}
if(stack.isEmpty())
return true;
return false;
}
public static void main(String[] args) {
String s = "(([()]))[]";
System.out.println(new ValidParentheses().isValid(s));
}
}