n = int(eval(input()))

for i in range(n+1):

    if (i+1)**2 > n:

        print((i**2))

        exit()
n = int(eval(input()))

l = 0

r = n + 1



while l + 1 < r:

    m = l + (r - l) // 2

    if m**2 > n:

        r = m

    else:

        l = m

print((l**2))

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

n = int(eval(input()))
l = 0
r = n + 1
while l + 1 < r:
    m = l + (r - l) // 2
    if m**2 > n:
        r = m
    else:
        l = m
print((l**2))

-for i in range(n + 1): -    if (i + 1) ** 2 > n: -        print((i**2)) -        exit() +l = 0 +r = n + 1 +while l + 1 < r: +    m = l + (r - l) // 2 +    if m**2 > n: +        r = m +    else: +        l = m +print((l**2))