백준 - 2292 벌집 풀이

07 Jun 2022

Reading time ~1 minute

문제

2292 벌집

풀이

y = 1 / 0 < x <= 1
- 1 = 1 + 6 * 0
  - 0 = 0
y = 2 / 1 < x <= 7
- 7 = 1 + 6 * 1
  - 1 = 0 + 1
y = 3 / 7 < x <= 19
- 19 = 1 + 6 * 3
  - 3 = 0 + 1 + 2
y = 4 / 19 < x <= 37
- 37 = 1 + 6 * 6
  - 6 = 0 + 1 + 2 + 3
y = 5 / 37 < x <= 61
- 61 = 1 + 6 * 10
  - 10 = 0 + 1 + 2 + 3 + 4

답

kotlin code

import java.util.*

fun main() {
    q2292()
}

fun q2292() = with(Scanner(System.`in`)) {
    val input = nextInt()
    
    var i = 0
    while (input > (6 * sumOfAllNaturalNumbersLessThan(i)) + 1) {
        i++
    }
    println(i + 1)
}

fun sumOfAllNaturalNumbersLessThan(x: Int): Int {
    var sum = 0
    for(i in 1..x) {
        sum += i
    }
    return sum
}

baekjoon kotlin 코틀린 백준 브론즈 수학 풀이