백준 - 2292 벌집 풀이

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
}