N = int(input())
C,V = map(int,input().split())
# コピーを何回やるか

cp = C+V
ans = float('INF')
for i in range(1,60):
    moji = 2**(i)
    cost = cp*i
    pmoji = 2**(i-1)
    if moji >= N:
        ans = min(ans,cost)
    else:
        cost += -(-(N-moji)//pmoji)*V
        ans = min(ans,cost)

print(ans)