Max Number Of Balloons

Given a string text, you want to use the characters of text to form as many instances of the word "balloon" as possible. You can use each character in text at most once. Return the maximum number of instances that can be formed.

Input: text = "nlaebolko"; Output: 1

Source

package questions

import kotlin.test.assertEquals

/**
 * Given a string text, you want to use the characters of text to form as many instances of the word "balloon" as possible.
 * You can use each character in text at most once. Return the maximum number of instances that can be formed.
 *
 * Input: text = "nlaebolko"; Output: 1
 *
 * [Source](https://leetcode.com/explore/item/3973)
 */
fun maxNumberOfBalloons(text: String): Int {
    if (text.length < "balloon".length)
        return 0

    val balloon = arrayOf(0, 0, 0, 0, 0, 0, 0)
    // OR use when
    val strategy: Map<Char, () -> Unit> = mapOf(
        'b' to { balloon[0]++ },
        'a' to { balloon[1]++ },
        'n' to { balloon[6]++ },
        'l' to {
            if (balloon[2] == balloon[3]) {
                balloon[2]++
            } else if (balloon[2] < balloon[3]) {
                balloon[2]++
            } else {
                balloon[3]++
            }
        },
        'o' to {
            if (balloon[4] == balloon[5]) {
                balloon[4]++
            } else if (balloon[4] < balloon[5]) {
                balloon[4]++
            } else {
                balloon[5]++
            }
        }
    )
    text.forEach {
        strategy[it]?.invoke()
    }
    return balloon.minByOrNull { it }!!
}

fun main() {
    assertEquals(1, maxNumberOfBalloons("nlaebolko"))
    assertEquals(2, maxNumberOfBalloons("loonbalxballpoon"))
    assertEquals(0, maxNumberOfBalloons("leetcode"))
    assertEquals(1, maxNumberOfBalloons("balloon"))
    assertEquals(3, maxNumberOfBalloons("balloonballoonballoon"))
}

---

View on GitHub

Updated on 2021-09-13