Submission #333790

#	Time	Username	Problem	Language	Result	Execution time	Memory
333790		limabeans	Odd-even (IZhO11_oddeven)	Cpython 3	100 / 100	16 ms	2924 KiB

oddeven

def asum(x):
    return x*(x+1)//2


def f(i):
    return asum(i)



n = int(input())
if n==1:
    print(1)
else :
    lo = 1
    hi = n
    while hi-lo>1:
        mid = (lo+hi)//2
        if f(mid) < n:
            lo = mid
        else:
            hi = mid

    i = lo
    n -= f(i)
    n -= 1 # 0-index
    cur = asum(i)+asum(i-1) + 1 + 2*n
    print(cur)

• Subtask 1: 100 / 100