h2-computing-notes/code/data_structures/circular_queue.py at main · LimMengShin/h2-computing-notes · GitHub

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
class CircularQueue:
    def __init__(self, max_size):
        self.max_size = max_size
        self.queue = [None]*max_size
        self.front = 0
        self.rear = 0

    def is_empty(self):
        return self.front == self.rear

    def is_full(self):
        return (self.rear + 1) % self.max_size == self.front

    def enqueue(self, data):
        if self.is_full():
            print("cannot enqueue. queue full.")
        else:
            self.rear = (self.rear + 1) % self.max_size
            self.queue[self.rear] = data

    def dequeue(self):
        if self.is_empty():
            return "cannot dequeue. queue empty."
        else:
            dequeued_item = self.queue[self.front]
            self.front = (self.front + 1) % self.max_size
            return dequeued_item


    def display(self):
        curr_ptr = self.front
        while curr_ptr != self.rear:
            print(self.queue[curr_ptr])
            curr_ptr = (curr_ptr + 1) % self.max_size

    def display_raw(self):
        print(self.queue)
        print(self.front, self.rear)


#main
circular_queue = CircularQueue(3)
circular_queue.display_raw()
circular_queue.display()

#insert 1 item
print("Enqueue a:")
circular_queue.enqueue('a')
circular_queue.display_raw()
circular_queue.display()

#insert 1 item
print("Enqueue b:")
circular_queue.enqueue('b')
circular_queue.display_raw()
circular_queue.display()

#delete 1 item
print("Dequeue:")
print("Deleted: " + circular_queue.dequeue())
circular_queue.display_raw()
circular_queue.display()

#delete 1 item
print("Dequeue:")
print("Deleted: " + circular_queue.dequeue())
circular_queue.display_raw()
circular_queue.display()

#delete 1 item
print("Dequeue:")
print("Deleted: " + circular_queue.dequeue())
circular_queue.display_raw()
circular_queue.display()

#insert 1 item
print("Enqueue c:")
circular_queue.enqueue('c')
circular_queue.display_raw()
circular_queue.display()

#insert 1 item
print("Enqueue d:")
circular_queue.enqueue('d')
circular_queue.display_raw()
circular_queue.display()

#insert 1 item
print("Enqueue e:")
circular_queue.enqueue('e')
circular_queue.display_raw()
circular_queue.display()

#insert 1 item
print("Enqueue f:")
circular_queue.enqueue('f')
circular_queue.display_raw()
circular_queue.display()

#delete 1 item
print("Dequeue:")
print("Deleted: " + circular_queue.dequeue())
circular_queue.display_raw()
circular_queue.display()

#insert 1 item
print("Enqueue f:")
circular_queue.enqueue('f')
circular_queue.display_raw()
circular_queue.display()