Circular Queue

Lab C Advanced 30 points

Implement a queue of capacity 4 with a circular array (front index and count). Commands: enq X (print full if full), deq (print the value or empty). Finally print the remaining items in order.

Input

n, then n commands.

Output

Messages, then the remaining items (or none).

Example

Input

8
enq 1
enq 2
enq 3
enq 4
enq 5
deq
enq 6
deq

Output

full
1
2
3 4 6

Sample input available Sample output available

Editor

Hints

The back position is (front + count) % CAP.

Wrapping with % reuses freed slots.

Solution explanation

A circular buffer gives a fixed-size queue without ever shifting elements.

Show solution

#include <stdio.h>
#include <string.h>
#define CAP 4

int q[CAP];
int front = 0;
int count = 0;

int main() {
    int n, x;
    char cmd[10];
    scanf("%d", &n);
    for (int i = 0; i < n; i++) {
        scanf("%s", cmd);
        if (strcmp(cmd, "enq") == 0) {
            scanf("%d", &x);
            if (count == CAP) printf("full\n");
            else {
                q[(front + count) % CAP] = x;
                count++;
            }
        } else {
            if (count == 0) printf("empty\n");
            else {
                printf("%d\n", q[front]);
                front = (front + 1) % CAP;
                count--;
            }
        }
    }
    if (count == 0) printf("none\n");
    for (int i = 0; i < count; i++) printf("%d%s", q[(front + i) % CAP], i < count - 1 ? " " : "\n");
    return 0;
}

Output

Answer