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class Solution {
    public Node intersect(Node quadTree1, Node quadTree2) {
        if (quadTree1.isLeaf) {
            if (quadTree1.val == true) {
                return quadTree1;
            } else {
                return quadTree2;
            }
        }

        if (quadTree2.isLeaf) {
            if (quadTree2.val == true) {
                return quadTree2;
            } else {
                return quadTree1;
            }
        }

        Node topLeft = intersect(quadTree1.topLeft, quadTree2.topLeft);
        Node topRight = intersect(quadTree1.topRight, quadTree2.topRight);
        Node bottomLeft = intersect(quadTree1.bottomLeft, quadTree2.bottomLeft);
        Node bottomRight = intersect(quadTree1.bottomRight, quadTree2.bottomRight);

        if (topLeft.isLeaf == true &&
                topRight.isLeaf == true &&
                bottomLeft.isLeaf == true &&
                bottomRight.isLeaf == true &&
                topLeft.val == topRight.val &&
                topLeft.val == bottomLeft.val &&
                topLeft.val == bottomRight.val &&
                topLeft.val == bottomRight.val
        ) {
            return new Node(topLeft.val, true);
        } else {
            return new Node(false, false, topLeft, topRight, bottomLeft, bottomRight);
        }
    }
}