가장 긴 공통 접두사 찾기

fun longestCommonPrefix(strs: List<String>): String {
    if (strs.isEmpty()) return ""
    val prefix = StringBuilder()
    strs.reduce { acc, s -> acc.commonPrefixWith(s) }.forEach { prefix.append(it) }
    return prefix.toString()
}

fun main() {
    println(longestCommonPrefix(listOf("flower", "flow", "flight"))) // "fl"
}