[LeetCode] 20. Valid Parentheses | 자바스크립트

[LeetCode] 20. Valid Parentheses 타입스크립트

✍️ 문제

Given a string s containing just the characters '(', ')', '{', '}', '[' and ']', determine if the input string is valid.

An input string is valid if:

1. Open brackets must be closed by the same type of brackets.
2. Open brackets must be closed in the correct order.
3. Every close bracket has a corresponding open bracket of the same type.

 

Example 1:

Input: s = "()"
Output: true

Example 2:

Input: s = "()[]{}"
Output: true

Example 3:

Input: s = "(]"
Output: false

 

Constraints:

• 1 <= s.length <= 104
• s consists of parentheses only '()[]{}'.

🖥 해결방법

function isValid(s: string): boolean {
    const stack = [];
    
    for (const c of s) {
        if (c === '(' || c === '{' || c === '[') {
            stack.push(c);
        } else {
            const p = stack.pop();
            
            if (c === ')' && p !== '(' || c === '}' && p !== '{' || c === ']' && p !== '[') return false;
        }
    }
    
    return stack.length === 0;
};

🌈 결과