from heapq import heapify, heappop, heappush

n = int(input())
c, v = map(int, input().split())

H = [(c, 1, 1)]
INF = 10**18
DP = [INF for _ in range(n + 1)]
DP[1] = c
heapify(H)
while H:
    cost, num, c_num = heappop(H)
    if num >= n:
        print(cost)
        break
    if c_num != num:
        if cost + c + v < DP[min(num * 2, n)]:
            DP[min(num * 2, n)] = cost + c + v
            heappush(H, (cost + c + v, num * 2, num))
    if cost + v < DP[min(num + c_num, n)]:
        DP[min(num + c_num, n)] = cost + v
        heappush(H, (cost + v, num + c_num, c_num))