import sys
input = lambda : sys.stdin.readline().rstrip()

sys.setrecursionlimit(2*10**5+10)
write = lambda x: sys.stdout.write(x+"\n")
debug = lambda x: sys.stderr.write(x+"\n")
writef = lambda x: print("{:.12f}".format(x))


n,h,w = list(map(int, input().split()))
def sub(h,v):
    v0 = v//2
    v1 = v//2 + v%2
    ans = h * v0 * v1
    return ans
ans = sub(h-1,n) + sub(w-1,n)
print(ans)