From cf8cc6d48d72b3605c329bb73a73b12920336047 Mon Sep 17 00:00:00 2001
From: Swami Patil <scpatil670@gamil.com>
Date: Sat, 7 Dec 2024 21:39:54 +0530
Subject: [PATCH] Added Queue Data Structure

---
 Data Structure Using C/queue/queue.c | 89 ++++++++++++++++++++++++++++
 1 file changed, 89 insertions(+)
 create mode 100644 Data Structure Using C/queue/queue.c

diff --git a/Data Structure Using C/queue/queue.c b/Data Structure Using C/queue/queue.c
new file mode 100644
index 00000000..9fe87fe9
--- /dev/null
+++ b/Data Structure Using C/queue/queue.c	
@@ -0,0 +1,89 @@
+#include <stdio.h>
+#define maxsize 10
+
+int queue[maxsize], front = -1, rear = -1;
+
+void enqueue();
+void dequeue();
+void display();
+
+int main()
+{
+    int choice;
+    
+    do
+    {
+        printf("\n----queue----\n");
+        printf("Press 1 for enqueue\n");
+        printf("Press 2 for dequeue\n");
+        printf("Press 3 for display\n");
+        printf("Press 4 for exit\n");
+        printf("Enter your choice: ");
+        scanf("%d", &choice);
+        
+        switch(choice)
+        {
+            case 1: enqueue(); break;
+            case 2: dequeue(); break;
+            case 3: display(); break;
+            case 4: break;
+            default: printf("Invalid choice\n");
+        }
+    } while(choice != 4);
+
+    return 0;
+}
+
+void enqueue()
+{
+    if (rear == maxsize - 1) 
+    {
+        printf("Queue is overflow\n");
+    } 
+    else 
+    {
+        if (front == -1) 
+            front = 0;  // Initialize front when first element is added
+        
+        printf("Enter value: ");
+        rear++;
+        scanf("%d", &queue[rear]);
+    }
+}
+
+void dequeue()
+{
+    if (front == -1 || front > rear) 
+    {
+        printf("Queue is empty\n");
+    } 
+    else 
+    {
+        printf("Deleted item: %d\n", queue[front]);
+        front++;
+        
+        // Reset front and rear if queue becomes empty
+        if (front > rear) 
+        {
+            front = -1;
+            rear = -1;
+        }
+    }
+}
+
+void display()
+{
+    if (front == -1 || front > rear) 
+    {
+        printf("Queue is empty\n");
+    } 
+    else 
+    {
+        printf("Queue elements: ");
+        for (int i = front; i <= rear; i++) 
+        {
+            printf("%d\t", queue[i]);
+        }
+        printf("\n");
+    }
+}