def check(Fib, AA, i):
    ret = 0
    for j in range(5):
        if Fib[i+j] == AA[j]:
            ret += 1
        else:
            break
    return ret

fib = [1,1]
for _ in range(100):
    fib.append(fib[-2]+fib[-1])

A = []
for _ in range(5):
    A.append(int(input()))
    
A = A[::-1]

ans = 0

if A[0] in fib:
    ind = fib.index(A[0])
    ans = check(fib, A, ind)
    
if A[0] == 1:
    ans = max(ans, check(fib, A, ind+1))
        
print(ans)