Tops at iTunes

The top singles on iTunes for the week ending Feb 17.

1. "Happy (from 'Despicable Me 2')," Pharrell Williams

2. "Dark Horse," Katy Perry, featuring Juicy J

3. "Talk Dirty," Jason Derulo, featuring 2 Chainz

4. "All of Me,"

John Legend, above

5. "Pompeii," Bastille