def is_kadomatsu(lst):
    if len(set(lst)) != 3:
        return False
    return min(lst) == lst[1] or max(lst) == lst[1]

lst = list(map(int,input().split()))
i = 2
cnt = 0
t_chain = 0
f_chain = 0
while True:
    if is_kadomatsu([x % i for x in lst]):
        cnt+=1
        t_chain+=1
        f_chain = 0
    else:
        f_chain+=1
        t_chain = 0
    if t_chain >= 100 or f_chain >= 100:
        break
    i+=1
if t_chain >= 100:
    ans = "INF"
else:
    ans = cnt
print(ans)