One flat in the key signature, like the relative major of F
major.
It is written here with accidentals and no key signature at
the beginning.
Note that F major has B flat in the key signature. As the 6th. and 7th. notes
are raised in melodic minor scale,
the B flat becomes a B natural, followed by C sharp.
Click twice to hear it.
The 6th. and 7th. notes are lowered again going
down the scale.
Note the same pattern as for A melodic minor.
step, half-step, step, step, step, step,
half-step.