This song by Bruno Mars is in B.
These are the “cheat” chords I played…
Part 1a: B - F# - E2
Part 1b: same as Part 1a
Part 1c: same as Part 1a
Part 1d: same as Part 1a
Part 2: C#m7 - B/D# - E2 - F#
Part 3a: B - F# - E2
Part 3b: same as Part 3a
Part 3c: [...]
