from heapq import *

N = int(input())
C, V = map(int, input().split())
INF = 10 ** 8
D = [INF] * (N + 1)
D[1] = C
Q = [(C + V, 2, 1)]
D[2] = C + V
while Q:
    cost, i, cp = heappop(Q)
    if cost > D[i]: continue
    if D[min(N, i + cp)] > D[i] + V:
        D[min(N, i + cp)] = D[i] + V
        if N > i + cp:
            heappush(Q, (D[i + cp], i + cp, cp))
    if D[min(N, 2 * i)] > D[i] + C + V:
        D[min(N, 2 * i)] = D[i] + C + V
        if N > 2 * i:
            heappush(Q, (D[2 * i], 2 * i, cp))
print(D[N])