Given a string s containing just the characters '(', ')', '{', '}', '[' and ']', determine if the input string is valid.
An input string is valid if:
- Open brackets must be closed by the same type of brackets.
- Open brackets must be closed in the correct order.
Example 1:
Input: s = "()" Output: true
Example 2:
Input: s = "()[]{}"
Output: true
Example 3:
Input: s = "(]" Output: false
Example 4:
Input: s = "([)]" Output: false
Example 5:
Input: s = "{[]}"
Output: true
Constraints:
1 <= s.length <= 104sconsists of parentheses only'()[]{}'.
Note:
Your algorithm should run in O(n) time and use O(n) extra space.
Walkthroughs of the solution. Try the steps first, then watch to compare approaches.
Free plan: 30 tutor messages. Premium is unlimited.
Saved
Ctrl + Enter to check