Add valid parentheses Solution - s0ooo0k

Author: s0ooo0k

valid-parentheses/s0ooo0k.java

@@ -0,0 +1,26 @@
+class Solution {
+    public boolean isValid(String s) {
+        Deque<Character> stack = new ArrayDeque<>();
+
+        for(char c : s.toCharArray()) {
+            if(c == '(' || c=='{' || c=='[') {
+                stack.push(c);
+            }
+            if(c == ')') {
+                if(stack.isEmpty() || stack.peek() != '(') return false;
+                 stack.pop();
+            }
+            if(c == '}') {
+                if(stack.isEmpty() || stack.peek() != '{') return false;
+                stack.pop();
+            }
+            if(c == ']') {
+                if(stack.isEmpty() || stack.peek() != '[') return false;
+                stack.pop();    
+            }
+        }
+        return stack.isEmpty();
+    }
+}
+
+