计算每行所占字符个数，并格式化输出

import scala.io.Source

def widthOfLength(s: String) = s.length.toString.length//计算字符串长度的位数，比如长度为：136，则位数为：3（三位数）
if (args.length > 0) {
    val lines = Source.fromFile(args(0)).getLines.toList
    val longestLine = lines.reduceLeft(
        (a, b) => if (a.length > b.length) a else b
    )
    val maxWidth = widthOfLength(longestLine)
    for (line <- lines) {
        val numSpaces = maxWidth - widthOfLength(line)
        val padding = " " * numSpaces
        println(padding + line.length + "|" + line)
    }
}else
    Console.err.println("Please enter filename")