2-3-4 Tree .python

class BTreeNode:
    def __init__(self, leaf=True):
        self.leaf = leaf
        self.keys = []
        self.children = []

    def display(self, level=0):
        print(f"Level {level}: {self.keys}")
        if not self.leaf:
            for child in self.children:
                child.display(level + 1)

class BTree:
    def __init__(self, t):
        self.root = BTreeNode(True)
        self.t = t

    def insert(self, k):
        root = self.root
        if len(root.keys) == (2 * self.t) - 1:
            temp = BTreeNode()
            self.root = temp
            temp.children.append(root)
            self.split_child(temp, 0)
            self.insert_non_full(temp, k)
        else:
            self.insert_non_full(root, k)

    def insert_non_full(self, x, k):
        # Implementation of insertion in a non-full node
        # ...

    def split_child(self, x, i):
        # Implementation of splitting a child node
        # ...

def main():
    B = BTree(3)
    keys = [10, 20, 5, 6, 12, 30, 7, 17]
    for key in keys:
        B.insert(key)
    print("B-tree structure:")
    B.display()

if __name__ == '__main__':
    main()