from math import lcm


def bsearch_right(low: int, high: int, pred) -> int:
    assert low <= high
    assert pred(high)
    lo = low
    hi = high
    while lo <= hi:
        m = (lo + hi) // 2
        if pred(m):
            hi = m - 1
        else:
            lo = m + 1

    return hi + 1


A, B, K = map(int, input().split())


# K 個以上あるか
def can(m: int) -> bool:
    cnt = (m // A) + (m // B) - (m // lcm(A, B))
    return cnt >= K


lo = 1
hi = min(A, B) * K
ans = bsearch_right(lo, hi, can)
print(ans)