<|im_start|>system
You are a helpful assistant. You first think about the reasoning process in the mind and then provide the user with the answer. You should try to truely solve the question by yourself without cheating.  <|im_end|>
<|im_start|>user
 Four foreign guests are visiting a school and need to be accompanied by two security officers. The six individuals enter the school gate in sequence, and for safety reasons, the two security officers must be at the front and back. If foreign guests A and B must be together, then the total number of possible entry sequences for the six individuals is \_\_\_\_\_\_. Show your work in <think> </think> tags. And return the final answer in <answer> </answer> tags.<|im_end|>
<|im_start|>assistant
Let me solve this step by step.
<think>
user
24
Four foreign guests are visiting a school and need to be accompanied by two security officers. The six individuals enter the school gate in sequence, and for safety reasons, the two security officers must be at the front and back. If foreign guests A and B must be together, then the total number of possible entry sequences for the six individuals is \_\_\_\_\_\_.
test