Feat: 20. Valid Parentheses

Author: HC-kang

valid-parentheses/HC-kang.ts

@@ -0,0 +1,17 @@
+/**
+ * https://leetcode.com/problems/valid-parentheses
+ * T.C. O(n)
+ * S.C. O(n)
+ */
+function isValid(s: string): boolean {
+  const pairs: Record<string, string> = { '{': '}', '[': ']', '(': ')' };
+  const stack: string[] = [];
+
+  if (s.length % 2 == 1) return false;
+
+  for (const char of s) {
+    if (pairs[char]) stack.push(char);
+    else if (char != pairs[stack.pop()!]) return false;
+  }
+  return !stack.length;
+}