Valid Parentheses solution

Author: jdy8739

valid-parentheses/jdy8739.js

@@ -0,0 +1,30 @@
+/**
+ * @param {string} s
+ * @return {boolean}
+ */
+var isValid = function(s) {
+    const stack = [];
+
+    for (let i=0; i<s.length; i++) {
+        const cur = s[i];
+
+        if (cur === '(' || cur === '[' || cur === '{') {
+            stack.push(cur);
+        } else {
+            const topOfStack = stack[stack.length - 1];
+
+            const caseA = topOfStack === '(' && cur === ')';
+            const caseB = topOfStack === '[' && cur === ']';
+            const caseC = topOfStack === '{' && cur === '}';
+
+            if (caseA || caseB || caseC) {
+                stack.pop();
+            } else {
+                return false;
+            }
+        }
+    }
+
+    return stack.length === 0;
+};
+