java-programs/Stack.java at master · modkhalid/java-programs · 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
package coding;

public class Stack {
	protected int top;
	protected int[] data;

	public Stack() {
		this(5);
	}

	public Stack(int cap) {
		data=new int[cap];
		top=-1;
	}


	public void push(int item) throws Exception {
		if(this.size()==this.data.length) {
			throw new Exception("Stack Over flow");
		}
		++top;
		this.data[this.top]=item;
	}


	public int pop() throws Exception {
		if(this.size()==0) {
			throw new Exception("Stack is Empty");
		}
		int temp=this.data[this.top];
		this.data[this.top]=0;
		this.top--;
		return temp;


	}


	public int top() throws Exception {
		if(this.size()==0) {
			throw new Exception("Stack is Empty");
		}
		int temp=this.data[this.top];
//		this.data[this.top]=0;
//		this.top--;
		return temp;
	}


	public int size() {
		return this.top+1;
	}

	public boolean isEmpty() {
		return this.size()==0;
	}

	public void display() {
		for (int i = 0; i <= this.top	; i++) {
			System.out.print(this.data[i]+" ");
		}
		System.out.println();
	}

}