Update README.md

abroroo · web-flow · commit 342c295a56fb · 2023-03-01T00:27:36.000+09:00
diff --git a/README.md b/README.md
@@ -4,6 +4,26 @@ List is periodically updated
 
 ## LeetCode
 
+### #20 Valid Parentheses
+```
+var isValid = function(s) {
+    let stack = [];
+
+    for(let i = 0; i < s.length; i++){
+        if(s[i] == '('){
+            stack.push(')');
+        } else if (s[i] == '{'){
+            stack.push('}');
+        } else if (s[i] == '['){
+            stack.push(']');
+        } else if (stack.pop() !== s[i]){
+            return false
+        }   
+    }
+    return !stack.length
+};
+
+```
 ### #14 Longest Common Prefix
 ```
 
