Submission #676517

#	Time	Username	Problem	Language	Result	Execution time	Memory
676517		QwertyPi	Odd-even (IZhO11_oddeven)	Cpython 3	100 / 100	16 ms	2908 KiB

oddeven

from math import sqrt
n = int(input())

def isqrt(n):
    x = n
    y = (x + 1) // 2
    while y < x:
        x = y
        y = (x + n // x) // 2
    return x


x = isqrt(n * 2)

while x * (x - 1) // 2 >= n:
    x -= 1
while x * (x + 1) // 2 < n:
    x += 1
print(n * 2 - x)

• Subtask 1: 100 / 100