Stair Game

There is a staircase consisting of n stairs, numbered 1,2,\ldots,n. Initially, each stair has some number of balls. There are two players who move alternately. On each move, a player chooses a stair k where k \neq 1 and it has at least one ball. Then, the player moves any number of balls from stair k to stair k-1. The player who moves last wins the game. Your task is to find out who wins the gam