답안 #333789

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
333789 2020-12-07T19:26:01 Z limabeans 홀-짝 수열 (IZhO11_oddeven) Python 3
0 / 100
30 ms 3948 KB
import sys
from math import *
from fractions import gcd
from random import * # randint(inclusive,inclusive)
readints=lambda:map(int, input().strip('\n').split())
from itertools import permutations, combinations
ALP = "abcdefghijklmnopqrstuvwxyz"
# print('', end=" ")
# for i in {1..5}; do echo "hi"; done

def randarr(n, lo, hi):
    assert(lo<=hi)
    return [randint(lo,hi) for _ in range(n)]


def randstr(n):
    s=''
    for _ in range(n):
        s += ALP[randint(0,25)]
    return s
    

def randtree(n):
    pass


##############################################################################


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)





# 결과 실행 시간 메모리 Grader output
1 Runtime error 30 ms 3948 KB Execution failed because the return code was nonzero
2 Halted 0 ms 0 KB -