Rotate Parentheses / 심화

Author: oh-chaeyeon

oh-chaeyeon/2주차_스택/Rotate_Parentheses.js

@@ -0,0 +1,25 @@
+function solution(s) {
+  let answer = 0;
+  for (let i = 0; i < s.length; i++) {
+    const rotated = s.slice(i) + s.slice(0, i);
+    if (isValid(rotated)) answer++;
+  }
+  return answer;
+}
+
+function isValid(str) {
+  const stack = [];
+  for (let c of str) {
+    if ("([{".includes(c)) stack.push(c);
+    else if (!stack.length || !isPair(stack.pop(), c)) return false;
+  }
+  return stack.length === 0;
+}
+
+function isPair(open, close) {
+  return (
+    (open === "(" && close === ")") ||
+    (open === "[" && close === "]") ||
+    (open === "{" && close === "}")
+  );
+}