from math import ceil

N,X,T = list(map(int,input().split(' ')))

p = ceil(N/X)

print((p*T))
from math import ceil 

N,X,T = list(map(int,input().split(' ')))

print((ceil(N/X)*T))
from math import ceil

N, X, T = list(map(int, input().split(" ")))
p = ceil(N / X)
print((p * T))

from math import ceil

N, X, T = list(map(int, input().split(" ")))
print((ceil(N / X) * T))

-p = ceil(N / X) -print((p * T)) +print((ceil(N / X) * T))