Submission #170706

#	Time	Username	Problem	Language	Result	Execution time	Memory
170706		Lightning	Odd-even (IZhO11_oddeven)	Cpython 3	100 / 100	27 ms	3428 KiB

oddeven

# your code goes here
def sum(n):
	return (n * (n + 1) // 2)

n = int(input())
l = 1
r = n
while(l < r):
	mid = (l + r) // 2
	if(sum(mid) >= n):
		r = mid
	else:
		l = mid + 1
fir = (r * (r - 2)) + 2
pos = n - sum(r - 1)
print(fir + (2 * (pos - 1)))

• Subtask 1: 100 / 100