Tree Traversals Again

def solve(operations):
    stack = []
    preorder = []
    inorder = []
    for op in operations.split(';'):
        parts = op.split()
        if parts[0] == 'Push':
            stack.append(int(parts[1]))
            preorder.append(int(parts[1]))
        else:
            inorder.append(stack.pop())
    print(' '.join(map(str, inorder)))