"""

想定解

"""

N,H,W = map(int,input().split())

assert 2 <= N <= 10**9
assert 1 <= H <= 10**5
assert 1 <= W <= 10**5

A = N // 2 #(1,1)の人数
B = N - A  #(H,W)の人数

print ( ((H-1)+(W-1)) * A * B )