n = int(eval(input()))

for i in range(n+1):

  m = (i+1) ** 2

  if m > n:

    print((i**2))

    break
n = int(eval(input()))

print((int(n**0.5) ** 2))
n = int(eval(input()))
for i in range(n + 1):
    m = (i + 1) ** 2
    if m > n:
        print((i**2))
        break

n = int(eval(input()))
print((int(n**0.5) ** 2))

-for i in range(n + 1): -    m = (i + 1) ** 2 -    if m > n: -        print((i**2)) -        break +print((int(n**0.5) ** 2))