The input contains a single integer *a* (1 ≤ *a* ≤ 64).

Output a single integer.
The input contains a single integer *a* (1 ≤ *a* ≤ 64).
i = int(input(""))
for u in range(1,9):
    x = u*u
    if  x > u:
        print(u-1)
        break
    