Create QueueUsingTwoStacks.java

jumpman-cmd · web-flow · commit c07fac8b508d · 2024-09-16T19:23:29.000+02:00
diff --git a/QueueUsingTwoStacks.java b/QueueUsingTwoStacks.java
@@ -0,0 +1,58 @@
+/*
+
+*/
+
+import java.io.*;
+import java.util.*;
+
+public class QueueUsingTwoStacks 
+{
+    public static void main(String[] args) 
+    {
+        /* Enter your code here. Read input from STDIN. Print output to STDOUT. Your class should be named Solution. */
+        Scanner count = new Scanner(System.in);
+        int numberOfOperations = count.nextInt();
+        
+        Stack<Integer> stack1 = new Stack<>();
+        Stack<Integer> stack2 = new Stack<>();
+        
+        for(int i = 0; i < numberOfOperations; i++)
+        {
+            int typeOfOperation = count.nextInt();
+            
+            if(typeOfOperation == 1)
+            {
+                int addToQu = count.nextInt();
+                stack1.push(addToQu);
+            }
+            
+            else if(typeOfOperation == 2)
+            {
+                if(stack2.isEmpty())
+                {
+                    while(!stack1.isEmpty())
+                    {
+                        stack2.push(stack1.pop());
+                    }
+                }
+                
+                stack2.pop();
+            }
+            
+            else
+            {
+                if(typeOfOperation == 3 && stack2.isEmpty())
+                {
+                    while(!stack1.isEmpty())
+                    {
+                        stack2.push(stack1.pop());
+                    }
+                }
+                
+                System.out.println(stack2.peek());
+            }
+        }
+        
+        count.close();
+    }
+}
