Added Stack and Queue Algorithm

StackandQueue/queueusingarray.c

@@ -0,0 +1,87 @@
+#include<stdio.h>
+#include<stdbool.h>
+#include<stdlib.h>
+#define size 5
+
+int queue[size];
+int front = -1;
+int rear = -1;
+
+bool isEmpty()
+{
+	if(front == -1 && rear == -1)
+		return true;
+	return false;
+}
+
+bool isFull()
+{
+	if(rear == size-1)
+		return true;
+	return false;
+}
+
+void enQueue()
+{
+	int val;
+	if(isFull())
+		printf("Queue is FULL !!");
+	else if(isEmpty())
+	{
+		printf("\nEnter value : ");
+		scanf("%d",&val);
+		front = rear = 0;
+		queue[rear]=val;
+	}
+	else
+	{
+		printf("\nEnter value : ");
+		scanf("%d",&val);
+		rear++;
+		queue[rear]=val;
+	}
+	printf("\n");
+}
+
+void deQueue()
+{
+	if(isEmpty())
+		printf("\nQueue is EMPTY!!\n");
+	else if(front == rear)
+		front=rear=-1;
+	else
+		front ++;
+}
+
+void print()
+{
+	if(isEmpty())
+		printf("\nQueue is EMPTY!!\n");
+	else
+	{
+		for(int i=front;i<=rear;i++)
+			printf("%d ",queue[i]);
+	}
+	printf("\n");
+}
+int main()
+{
+	int choice; 
+	do
+	{
+		printf("ENTER CHOICE :\n1.Enqueue\n2.Dequeue\n3.Display\n4.Exit\n\n");
+		scanf("%d",&choice);
+		switch(choice)
+    	{
+			case 1: enQueue();
+	    	break;
+    		case 2: deQueue();
+	    	break;
+    		case 3: print();
+	   		break;
+    		case 4: exit(0);
+	    	break;
+		}
+   }while (choice!=4);
+   return 0;
+}

StackandQueue/queueusinglist.c

@@ -0,0 +1,95 @@
+#include<stdio.h>
+#include<stdlib.h>
+
+typedef struct node
+{
+	int data;
+	struct node *next;
+}node;
+
+node *head = NULL;
+
+node *createNode()
+{
+	node *temp;
+	temp = (node*)malloc(sizeof(node));
+	return temp;
+}
+
+void enQueue()
+{
+    node *temp = createNode();
+    printf ("Enter Your Data : ");
+    scanf ("%d",&temp->data);
+    temp->next=NULL;
+    if(head==NULL)
+        head=temp;
+    else 
+    {
+        node *t=head;
+    	while (t->next!=NULL)
+            t=t->next;
+    	t->next=temp;
+	}
+    printf("Data successfully Entered \n\n");
+
+}
+
+void deQueue()
+{
+	node *t=head;
+	node *del;
+	if(head==NULL)
+		printf("\nQueue is empty, UNDERFLOW!!\n");
+	else if(head->next==NULL)
+	{
+		del=head;
+		head=NULL;
+		printf("\n%d Popped from Queue\n\n",del->data);
+	}
+	else
+	{
+		del=head;
+		head=head->next;
+		printf("\n%d Popped from Queue\n\n",del->data);
+	}
+	free(del);
+}
+
+void print()
+{
+	if(head==NULL)
+	{
+		printf("Queue is EMPTY!!\n");
+		return;
+	}
+	node *t = head;
+	printf ("Data present in the Queue : \n");
+	while(t!=NULL)
+	{
+		printf ("%d \n",t->data);
+		t=t->next;
+	}
+}
+
+int main()
+{
+	int choice; 
+	do
+	{
+		printf("ENTER CHOICE :\n1.Enqueue\n2.Dequeue\n3.Display\n4.Exit\n\n");
+		scanf("%d",&choice);
+		switch(choice)
+    	{
+			case 1: enQueue();
+	    	break;
+    		case 2: deQueue();
+	    	break;
+    		case 3: print();
+	   		break;
+    		case 4: exit(0);
+	    	break;
+		}
+   }while (choice!=4);
+	return 0;
+}

StackandQueue/reame.md

@@ -0,0 +1,10 @@
+### Added Stack and Queue implementation
+Added the following programs :
+1. stackusingarray.c
+2. stackusinglist.c
+3. queueusingarray.c
+4. queueusinglist.c
+
+The following prorams are the implementation of **Stack** and **Queue** algorithms using array and linked list.
+
+**Cheers!**

StackandQueue/stackusingarray.c

@@ -0,0 +1,80 @@
+#include<stdio.h>
+#include<stdbool.h>
+#include<stdlib.h>
+#define MAX 5
+#define MIN -1
+
+int stack[MAX];
+int top = -1;
+
+bool notOverflow()
+{
+	if (top+1<MAX)
+		return true;
+	return false;
+}
+
+bool notUnderflow()
+{
+	if(top!=MIN)
+		return true;
+	return false;
+}
+
+void push()
+{
+	int val;
+	if (notOverflow())
+	{
+		printf("Enter Your Data : ");
+		scanf("%d",&val);
+		stack[++top]=val;
+	}
+	else
+	{
+		printf("\nSTACK OVERFLOW!!!\n\n");
+	}
+}
+
+void pop()
+{
+	if (notUnderflow())
+	{
+		printf("Popped Value : %d\n",stack[top--]);
+	}
+	else
+	{
+		printf("\nSTACK UNDERFLOW!!!\n\n");
+	}
+}
+
+void print()
+{
+	int i;
+	printf("\nData present in the stack : ");
+    for(i=0;i<=top;i++)
+    	printf("%d ",stack[i]);
+    printf("\n\n");
+}
+
+int main()
+{
+	int choice; 
+	do
+	{
+		printf("ENTER CHOICE :\n1.Push\n2.Pop\n3.Display\n4.Exit\n\n");
+		scanf("%d",&choice);
+		switch(choice)
+    	{
+			case 1: push();
+	    	break;
+    		case 2: pop();
+	    	break;
+    		case 3: print();
+	   		break;
+    		case 4: exit(0);
+	    	break;
+		}
+   }while (choice!=4);
+   return 0;
+}

StackandQueue/stackusinglist.c

@@ -0,0 +1,90 @@
+#include<stdio.h>
+#include<stdlib.h>
+
+typedef struct Stack
+{
+	int data;
+	struct Stack *next;
+}node;
+
+node *stack = NULL;
+
+node *createNode()
+{
+	node *temp;
+	temp = (node*)malloc(sizeof(node));
+	return temp;
+}
+
+void push()
+{
+    node *temp = createNode();
+    printf ("Enter Your Data : ");
+    scanf ("%d",&temp->data);
+    temp->next=NULL;
+    temp->next=stack;
+    stack=temp;
+    printf("\n\n%d Pushed into stack\n\n",temp->data);
+}
+
+void pop()
+{
+	node *t=stack;
+	node *del;
+	if(stack==NULL)
+		printf("\nStack is empty, UNDERFLOW!!\n");
+	else if(stack->next==NULL)
+	{
+		del=stack;
+		stack=NULL;
+		printf("\n\n%d Popped into stack\n\n",del->data);
+	}
+	else
+	{
+		del=stack;
+		stack=stack->next;
+		printf("\n\n%d Popped into stack\n\n",del->data);
+	}
+	free(del);
+}
+
+void print()
+{
+	if(stack==NULL)
+	{
+		printf("Stack is empty!!");
+		return 0;
+	}
+	node *t = stack;
+	int count = 0;
+	printf ("\nData present in the stack\n");
+	while(t!=NULL)
+	{
+		count++;
+		printf ("%d \n",t->data);
+		t=t->next;
+	}
+	printf("\nNumber of elements in the stack : %d\n\n",count);
+}
+
+int main()
+{
+	int choice; 
+	do
+	{
+		printf("ENTER CHOICE :\n1.Push\n2.Pop\n3.Display\n4.Exit\n\n");
+		scanf("%d",&choice);
+		switch(choice)
+    	{
+			case 1: push();
+	    	break;
+    		case 2: pop();
+	    	break;
+    		case 3: print();
+	   		break;
+    		case 4: exit(0);
+	    	break;
+		}
+   }while (choice!=4);
+   return 0;
+}