Valid Parentheses code

Author: Riya010107

Java/validParentheses.java

@@ -0,0 +1,46 @@
+import java.util.Scanner;
+import java.util.Stack;
+
+public class validParentheses {
+
+    public static void main(String[] args) {
+        
+        Scanner sc = new Scanner(System.in);
+        
+        // Get input
+        System.out.println("Enter a string of brackets:");
+        String str = sc.nextLine();
+        
+        boolean isValid = checkValidParentheses(str);
+        
+        if (isValid) {
+            System.out.println("The parentheses are valid!");
+        } else {
+            System.out.println("The parentheses are NOT valid!");
+        }
+    }
+    
+    
+    public static boolean checkValidParentheses(String s) {
+        Stack<Character> stack = new Stack<>();
+        
+        for (char ch : s.toCharArray()) {
+            if (ch == '(' || ch == '{' || ch == '[') {
+                stack.push(ch);
+            } else if (ch == ')' || ch == '}' || ch == ']') {
+                if (stack.isEmpty()) return false;
+                
+                char top = stack.pop();
+                
+                if ((ch == ')' && top != '(') ||
+                    (ch == '}' && top != '{') ||
+                    (ch == ']' && top != '[')) {
+                    return false;
+                }
+            }
+        }
+        
+        return stack.isEmpty();
+    }
+}
+