DSA/ArrayImplimentation.java at main · ZestyZeeshan/DSA · GitHub

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//import java.util.Stack;

//import java.util.Stack;

public class ArrayImplimentation {
    public static class Stack{


    private int[] arr=new int[5];
    int idx=0;
    void push(int x){
        arr[idx]=x;
        idx++;
    }
    int peek(){
        if(idx==0) {
            System.out.println("stck is empty");
            return -1;
        }
        return arr[idx-1];
    }
    int pop(){
        if(idx==0) {
            System.out.println("stck is empty");
            return -1;
        }
        int top=arr[idx-1];
        arr[idx-1]=0;
        idx--;
        return top;
    }
    void display(){
        for(int i=0;i<=idx-1;i++){
            System.out.println(arr[i]+" ");
        }
        System.out.println();
    }int size(){
        return idx;
    }
    boolean isEmpty(){
        if(size()==0)return true;
        else return false;
    }
}
    public static void main(String[] args) {
        Stack st=new Stack();
        st.push(4);
        st.display();
        st.push(5);
        st.display();
        st.push(6);
        st.display();
        st.pop();
        st.display();
        System.out.println(st.size());
       // System.out.println(st.size());

    }
}