from math import gcd

ceil = lambda a, b: (a + b - 1) // b
A, B, T = map(int, input().split())

if A * B // gcd(A, B) <= T:
    print(ceil(T, gcd(A, B)) * gcd(A, B))
    exit()

ans = 10 ** 9
a = 0
while (b := ceil(T - a * A, B)) >= 0:
    ans = min(ans, a * A + b * B)
    a += 1
print(ans)