Added dequeue.java and dequeue.py#3302
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soc221b
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soc221b
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Please rename file/directory to lowercase.
| System.out.println("Underflow"); | ||
| return -1; | ||
| } | ||
| int front_value=front.getValue(); |
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Please check variable naming: lowerCamelCase.
| } | ||
| int front_value=front.getValue(); | ||
| Node newFront = front.getNext(); | ||
| if(newFront!=null){ |
| private Node prev; | ||
| private Node next; | ||
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| public Node() { |
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Do we need this constructor?
I think this will be implicit error. Suppose that if someone compare the value, and the value is set to -1.
| rear.setNext(n); | ||
| n.setPrevious(rear); | ||
| rear = n; | ||
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| int frontValue = front.getValue(); | ||
| Node newFront = front.getNext(); | ||
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| if(newFront!=null) { |
| int rearValue = rear.getValue(); | ||
| Node newRear = rear.getPrevious(); | ||
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| if(newRear!=null){ |
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| public int removeRear() { | ||
| if (front == null) { | ||
| System.out.println("Underflow"); |
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In my opinion, this should implement with Exception.
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| public static void main(String args[]) { | ||
| Dequeue dq = new Dequeue(); | ||
| for(int i = 1; i <= 10; ++i){ |
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Every condition should be added space after the keyword.
| Dequeue dq = new Dequeue(); | ||
| for(int i = 1; i <= 10; ++i){ | ||
| dq.insertAtFront(i); | ||
| dq.insertAtRear(-1*i); |
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Should be -1 * i.
Add space around operators
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| for i in range(1,11): | ||
| print(dq.remove_front()) | ||
| print(dq.remove_rear()) |
| dq.insert_at_rear(-1*i); | ||
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| for i in range(1,11): | ||
| print(dq.remove_front()) |
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| if __name__ == '__main__': | ||
| dq = Dequeue(); | ||
| for i in range(1,11): |
| public class Dequeue { | ||
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| private Node front = null; | ||
| private Node rear = null; |
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The usual notation is head and tail.
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| public int removeFront() { | ||
| try { | ||
| int frontValue = front.getValue(); |
| front = newFront; | ||
| return frontValue; | ||
| } | ||
| catch (Exception e) { |
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A class should not catch an exception. That is the responsibility of the client. If you want to translate an exception, then catch it here, and rethrow your own copy. Don't print to the console.
| } | ||
| catch (Exception e) { | ||
| System.out.println("Underflow"); | ||
| return -1; |
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If you throw an exception, you won't need to return anything.
| rear = newRear; | ||
| return rearValue; | ||
| } | ||
| catch(Exception e) { |
| front = newFront; | ||
| return frontValue; | ||
| } | ||
| catch (Exception e) { |
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I disagree with this approach. Throw an exception for an empty container, as that is the idiomatic way to do things. Don't print to the console. Classes shouldn't even be catching exceptions. Let the client handle it. (It's less work for you anyways).
| rear = newRear; | ||
| return rearValue; | ||
| } | ||
| catch(Exception e) { |
| # Part of Cosmos by OpenGenus Foundation | ||
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| # Implementation using lists | ||
| class Dequeue: |
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I think we need front() and rear() also.
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not head and tail as suggested in java's code?
| container = [] | ||
| self.__container = container | ||
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| def insert_at_front(self, d): |
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Maybe push_front, push_back, pop_front, and pop_back is more prefer.
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| for i in range(1, 11): | ||
| print(dq.remove_front()) | ||
| print(dq.remove_rear()) |
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Remove trailing spaces at col: 37, and 38.
3 participants
Fixes issue: : #3243
Changes: : Added dequeue's implementation in java