Anne Hathaway and Hugh Jackman bonded over dieting during “Les Miserables.” At Tom Hooper’s film screenings Friday at Alice Tully Hall, Hathaway revealed that while she lost 25 pounds for her part, Jackman lost 30. “I can have half a potato for my next meal!” the actress recalled excitedly telling Jackman between takes. Hooper unveiled back-to-back screenings for guests including Harry Belafonte, Joel Coen, Howard Stringer, Scott Rudin, producer Eric Fellner and Elie Wiesel. The audience “applauded after each song like it was Broadway,” a spy said. We hear Hathway and co-star Samantha Barks sneaked off for karaoke during the second screening, where Russell Crowe slipped in, before returning for a Q&A. Amanda Seyfried recalled the cast’s intense vocal training, including a coach for each actor and no late nights out. Hooper and the cast then headed to LA, where there were six screenings of the Universal film over the weekend, and Barbra Streisand was spotted at one.