package leetcode_study

import io.kotest.matchers.equals.shouldBeEqual

import org.junit.jupiter.api.Test

class `encode-and-decode-strings` {

private val DELIMITER = ":"

fun encode(strings: List<String>): String {

return strings.joinToString(separator = "") { e -> "${e.length}$DELIMITER$e" }

}

fun decode(string: String): List<String> {

var index = 0

val result = mutableListOf<String>()

while (index < string.length) {

val delimiterIndex = string.indexOf(DELIMITER, startIndex = index)

val size = string.substring(index, delimiterIndex).toInt()

result.add(string.substring(delimiterIndex + 1, delimiterIndex + size + 1))

index = delimiterIndex + size + 1

}

return result

}

@Test

fun `문자열 목록을 하나의 문자열로 인코딩한다`() {

encode(listOf("leet","co:de","l:o:v:e","you")) shouldBeEqual "4:leet5:co:de7:l:o:v:e3:you"

}

@Test

fun `문자열을 문자열 목록으로 디코딩한다`() {

decode("4:leet5:co:de7:l:o:v:e3:you") shouldBeEqual listOf("leet","co:de","l:o:v:e","you")

}

}