N = int(eval(input()))

max=1

for i in range(1, N):

  if int(i**2)<=N:

    max=i**2

  else:

    break

print(max)
N = int(eval(input()))



print((int(N**(1/2))**2))
N = int(eval(input()))
max = 1
for i in range(1, N):
    if int(i**2) <= N:
        max = i**2
    else:
        break
print(max)

N = int(eval(input()))
print((int(N ** (1 / 2)) ** 2))

-max = 1 -for i in range(1, N): -    if int(i**2) <= N: -        max = i**2 -    else: -        break -print(max) +print((int(N ** (1 / 2)) ** 2))