N = int(eval(input()))

i = 1

ans = 1

while i**2 <= N:

    if i**2 <= N:

        ans = i**2

    i += 1

print(ans)
import math



N = int(eval(input()))

print((int(math.sqrt(N)) ** 2))
N = int(eval(input()))
i = 1
ans = 1
while i**2 <= N:
    if i**2 <= N:
        ans = i**2
    i += 1
print(ans)

import math

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

+import math + -i = 1 -ans = 1 -while i**2 <= N: -    if i**2 <= N: -        ans = i**2 -    i += 1 -print(ans) +print((int(math.sqrt(N)) ** 2))