Leetcode-GFG-Solutions/DeleteMiddleElementOfAStack.java at main · abhideepghosh/Leetcode-GFG-Solutions · GitHub

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// Iterative Method
class Solution
{
    //Function to delete middle element of a stack.
    public void deleteMid(Stack<Integer>s,int sizeOfStack){
        // code here

        Stack<Integer> tempStack = new Stack<>();

        int mid = sizeOfStack / 2;

        while(mid-- > 0){
            tempStack.push(s.pop());
        }
        s.pop();

        while(!tempStack.isEmpty()){
            s.push(tempStack.pop());
        }

    }
}


// Recursive Method
class Solution
{
    //Function to delete middle element of a stack.
    public void deleteMid(Stack<Integer>s,int sizeOfStack){
        // code here

        if(s.isEmpty()){
            return;
        }

        recursiveDeleteMid(s, sizeOfStack, 0);

    }

    public static void recursiveDeleteMid(Stack<Integer> stack, int sizeOfStack, int count){

        if(count >= sizeOfStack/2){
            stack.pop();
            return;
        }

        int currentValue = stack.peek();
        stack.pop();

        recursiveDeleteMid(stack, sizeOfStack, count + 1);

        stack.push(currentValue);

    }

}