The melody of The Days by Avicii runs 299 notes across 61 bars, 3:11 long in C at 125 beats per minute. The tab sits almost entirely in the first two frets, one note at a time — no chords to barre and no strumming pattern to keep up with. A piano backing track plays the chords and bass underneath, so the line you are learning sounds like the record even at half speed.
Prefer to strum and sing it instead? The Days chords and lyrics.