Shoot the Piano Player, Francois Truffaut's two-toned lament for a thin-skinned ivory-tickler. With Smiles of a Summer Night, a period comedy of lost aspirations--one of Bergman's best. Through March 2. The 400 Blows, the first Truffaut, a sensitive study of a tough youth's progress. 2:30, 6:05, 9:40, with Rules of the Game, beginning March 7.

East of Eden, Brattle Theatre, 5:30, 9:30. With Rebel Without a Cause. A James Dean pity-my-adolescent-agony double-bill. Dates badly. 7:30, 3:30 weekend.

Adrift, Jan Kadar's affected failure. 6, 9:25, With Firemens Ball, 8:05, 4:45 weekend. Central II.

The Conformist. One of the great ones: by Bernardo Bertollucci, with Dominique Sanda and Jean-Louis Trintignant.

Horse Feathers. Groucho Marx as a college president, Baker Aud., 8, March 2, 8, 10, March 3, $1. Long Days Journey Into Night, 8, 10:20, March 4, $1, High Noon, Classic Gary Cooper western, 8 March 5, $1.

The Bicycle Thief, Mather House dining hall. 8, 10, March 2. $1.

Lilith, with Warren Beatty, Jean Seberg and Peter Fonda. Hilles Cinema, 8, March 3.

Birth of a Nation with The General, Eliot House dining hall, 8, March 3 and 4. $1.

Kapo (Battle of Algiers), by Gillo Pontecorvo. Lowell dining hall. 7:30, 10, March 4. $1.

A Man Escaped by Robert Bresson, Harvard-Epworth Church. 7, March 2. $1. The Earrings of Madame de... by Max Ophuls. 7, March 5. $1.

Fiddler on the Roof. Topol's a fine Tevye, if that's your glass of tea. Cheri Complex. 8, Wed., Sat. and Sun., 1:30.

Cabaret, Minelli's spunky, Joel Grey appropriately unctuous, and Geoff Unsworth's camera helps out. Pretty good. Gary Theatre, 10, 12:30, 3, 5:30, 8, 10:10. Sun., 1, 3:15, 5:30, 8, 10:10.

Straw Dogs, the vilest, most talented American film of 1971. Garden Theatre. 6, 8, 10. Weekends, 2, 4, 6, 8, 10.

Hiroshima Mon, Amour, Dunster House, Resnais's first, best, Friday and Saturday, 8 & 10 p.m.

Minnie and Moscowitz, a film by John Cassavetes, Pi Alley, daily 1:30, 3:40, 5:50, 8, 10:10, Sun. at 3:20, 5:20, 7:30.

Dealing, fuzzy thinking about Harvard to Berkeley drug traffic, Savoy I, 426 Washington St. Every two hours 10 a.m. to p.m.

The French Connection, a good film about cops, the heavy side of Dealing, Saxon 219 Tremont St. Daily 12, 2, 4, 6, 8, 10, Sun. 1, 3, 5, 7, 9.

Macbeth, from Shakespeare with Polanski's assistance. Cinema Ken more Square. 644 Beacon St., daily 2, 7, 9:30.

Hospital, George C. Scott in another successful operation. Sack 57, 10, 12.2, 4, 6, 8, 10.

The Boyfriend, Twiggy's back, and now she sings too, Cheri III.