n = int(eval(input()))

c=[]

for i in range(n+1):

  a = i**2

  if a <= n:

    c.append(a)

  else:

    break

print((max(c)))
n = int(eval(input()))

print((int(n**(1/2))**2))
n = int(eval(input()))
c = []
for i in range(n + 1):
    a = i**2
    if a <= n:
        c.append(a)
    else:
        break
print((max(c)))

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

-c = [] -for i in range(n + 1): -    a = i**2 -    if a <= n: -        c.append(a) -    else: -        break -print((max(c))) +print((int(n ** (1 / 2)) ** 2))