45 minutes is a legal connection but gives you no "wiggle room". It will work only if your inbound flight arrives at the gate on-time. Will that happen??? Your guess is as good as mine.
If it were me, I'd opt for a longer connecting time. Remember, you are better off waiting an 30, 60 or more minutes for your connecting flight rather than arriving at the departure gate 1 minute after the plane leaves.
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