import collections,sys,math,functools,operator,itertools,bisect,heapq,decimal,string,time,random
#sys.setrecursionlimit(10**9)
#sys.set_int_max_str_digits(0)
#input = sys.stdin.readline
#n = int(input())
#alist = list(map(int,input().split()))
#alist = []
#s = input()
a,b,x = map(int,input().split())
#for i in range(n):
#    alist.append(list(map(int,input().split())))
for i in range(1,10000):
    if i * a >= x:
        print(i*b)
        exit()