Pistachio Salad

1 can crushed pineapple (with juice) -- 20 ounce can
1 box Pistachio instant pudding -- 3 ounce
1 cup mini-marshmallows
1 container cool whip -- 9 ounce

Stir together pineapple and instant pudding. Add marshmallows; stir in Cool Whip. chill