N = int(eval(input()))

for i in range(N,0,-1):

    if int(i**(1/2)) == i**(1/2):

        print(i)

        break
import math

print((int(math.sqrt(int(eval(input()))))**2))
N = int(eval(input()))
for i in range(N, 0, -1):
    if int(i ** (1 / 2)) == i ** (1 / 2):
        print(i)
        break

import math

print((int(math.sqrt(int(eval(input())))) ** 2))

-N = int(eval(input())) -for i in range(N, 0, -1): -    if int(i ** (1 / 2)) == i ** (1 / 2): -        print(i) -        break +import math + +print((int(math.sqrt(int(eval(input())))) ** 2))