from math import gcd, lcm

A, B, T = map(int, input().split())
ans = -(-T // A) * A

if T // B <= 10 ** 6:
    for x in range(-(-T//B) + 1):
        y = max(0,-((-T + B*x)//A))
        ans = min(ans,A*y+B*x)
    print(ans)
else:
    l = lcm(A, B)
    g = gcd(A, B)
    if l <= T:
        print(T + T % g)
    else:
        ans = l
        for x in range(-(-l // B) + 1):
            y = max(0, -((-T + B * x) // A))
            ans = min(ans, A * y + B * x)
        print(ans)