li = list(map(int, input().split()))

if li[0] % li[1] == 0:

    t = li[2] * (li[0] / li[1])

else:

    t = li[2] * (int(li[0] / li[1]) +1)

print((int(t)))

n, x, t = list(map(int, input().split()))



time = (n // x) * t

if n % x != 0:

    time += t



print(time)

li = list(map(int, input().split()))
if li[0] % li[1] == 0:
    t = li[2] * (li[0] / li[1])
else:
    t = li[2] * (int(li[0] / li[1]) + 1)
print((int(t)))

n, x, t = list(map(int, input().split()))
time = (n // x) * t
if n % x != 0:
    time += t
print(time)

-li = list(map(int, input().split())) -if li[0] % li[1] == 0: -    t = li[2] * (li[0] / li[1]) -else: -    t = li[2] * (int(li[0] / li[1]) + 1) -print((int(t))) +n, x, t = list(map(int, input().split())) +time = (n // x) * t +if n % x != 0: +    time += t +print(time)