How to arrange safety time reasonably

Monday, Tuesday, Wednesday, Thursday, Friday, Saturday and Sunday, security supervisor, morning shift, morning shift, night shift, morning shift, morning shift, morning shift, morning shift, night shift, night shift. The rules are as follows. Put the name of last week's security guard (4) in security guard (1), and move the other three security guards down one place in order. The supervisor has time to go to the early shift to replace the early shift security guard for an hour to eat and be on duty. When the supervisor is not at work, in principle, the security guard on the morning shift will take a 45-minute break with the security guard on the morning shift the day before to buy meals and take them to another security guard on the day shift (both parties can negotiate on their own). Who goes out to buy food is only a clear responsibility, not a dogma. )