3.5 Flexible Deque

#include<stdio.h>
#define q_s 3
int rear,front;
int queue[q_s];
void Insertion_R(int ele){
    if(front==0 && rear == q_s-1) {
        printf("\nQueue is full");
        return;
    }
    else if (rear==-1 && front == -1){
        rear = front = 0;
    }
    else if (front != 0 && rear == q_s-1 ){
        for(int i=front ; i<=rear ; i++){
            queue[i-1] = queue[i];
        }
        front--;
    }
    else rear++;
    queue[rear] = ele;
}

void Insertion_F(int ele){
    if(front==0 && rear == q_s-1) printf("\nQueue is full");
    else if (rear==-1 && front == -1) {
        rear = front = 0;
        queue[front] = ele;
    }
    else if (front == 0 && rear != q_s-1 ){
        for(int i=rear ; i>=front ; i--){
            queue[i+1] = queue[i];
        }
        rear++;
        queue[front] = ele;
    }
    else {
        queue[--front] = ele;
    }
}
void Deletion_F(){
    if(rear==-1) printf("\nQueue is already empty");
    else if (rear == front){
        queue[front]=0;
        rear = front = -1;
    }
    else queue[front++] = 0;
}
void Deletion_R(){
    if(rear == -1)printf("\nQueue is already empty");
    else if (rear == front){
        queue[rear] = 0;
        rear = front = -1;
    }
    else{
        queue[rear--] = 0;
    }
}
void Print(){
    if(rear == -1) {
        printf("\nQueue is empty");
        return;
    }
    for(int i = front ; i<=rear ; i++){
        printf("%d ",queue[i]);
    }
}
int main()
{
    rear = front = -1;
    int key,choice,element,id_choice;
    while(1){
        printf("\n1 for insertion \n2 for deletion\nAny key to just print the queue\n");
        scanf("%d",&choice);
        if(choice==1){
            printf("\nWhich insertion 1 - front and 2 - rear ");
            scanf("%d",&id_choice);
            if(id_choice == 1){
                printf("Enter the element ");
                scanf("%d",&element);
                Insertion_F(element);
            }
            else if(id_choice == 2){
                printf("Enter the element ");
                scanf("%d",&element);
                Insertion_R(element);
            }
        }
        else if(choice==2){
             printf("\nWhich deletion 1 - front and 2 - rear ");
            scanf("%d",&id_choice);
            if(id_choice == 1){
                Deletion_F();
            }
            else if(id_choice == 2){
                Deletion_R();
            }
        }
        else Print();

        printf("\n1 - for repeat and any key to exit ");
        scanf("%d",&key);
        if(key!=1)break;
    }
    return 0;
}