一道长度转换的题
前些日子报了某比赛，有个简单的测试。
length 题目介绍 您要做的是一个长度单位转化和计算工具，能够把不同的长度单位转换为标准长度（米），并且可以在不同单位之间进行加减运算。 输入文件 输入文件input.txt的内容可分为两部分： 不同单位和标准长度米的转换规则， 比如 1 mile = 1609.344 meters， 代表1英里等于1609.344米； 转换前或者计算前的单位，比如 1.2 miles // 一个长度 1.2 miles + 1 fath - 0.2 meters // 单位可能不同的长度之间的加减运算 您要做的 我们期望您编写一个应用程序，可以读取输入文件，了解不同单位与米之间的转换规则后，把以不同单位表示的长度都转换为标准单位米；同时计算不同单位长度的加减表达式，得到以米为单位的结果。 做题要求： 请一定Fork本仓库再做题目 使用的编程语言不限 输出结果为文件"output.txt"，其格式见下面说明 源代码和结果文件"output.txt"上传到您的GitHub代码库中 结果文件“output.txt”一定要放到代码库的根目录下 输出文件格式 该文件的格式共有12行，并严格遵守以下规则： 第1行是您的邮箱，比如 [email protected] 第2行是空行 第3行至第12行，每行显示1个计算结果，比如1931.21 m 计算结果要求精确到小数点后两位 计算结果均以字母m结尾，请注意数字和字母m之间有一个空格。
input.txt
1 mile = 1609.344 m 1 yard = 0.9144 m 1 inch = 0.00254 m 1 foot = 0.03048 m 1 fath = 1.8288 m 1 furlong = 201.17 m 1.2 miles 0.15 yard 32.7 inches 127.93 feet 22 faths 0.032 furlong 1 furlong + 2.5 feet 0.9 miles - 18 inches 1 fath - 1 foot + 12.5 inches 3.02 miles + 17.5 yards - 0 fath
题目非常简单，只是看到大家的方式，还是眼前一亮。
先说我自己做的：
package com.github.alaahong;
import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileReader;
import java.io.FileWriter;
import java.io.IOException;
import java.text.DecimalFormat;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import com.github.alaahong.FormatSeparator.FormatException;
public class Format {
/**
* @author Ian Zhang
* @param args
* @throws FormatException
* @throws NumberFormatException
* please use JDK1.7+
*/
public static void main(String[] args) throws NumberFormatException,
FormatException {
try {
// read file content from file
List<String[]> tempList = new ArrayList<String[]>();
List<Double> doubleList = new ArrayList<Double>();
Map<String, Double> tempMap = new HashMap<String, Double>();
FileReader reader = new FileReader(System.getProperty("user.dir")
+ File.separator + "input.txt");
BufferedReader br = new BufferedReader(reader);
String str = null;
int counter = 0;
while ((str = br.readLine()) != null) {
tempList.add(str.split(" "));
}
FormatSeparator fs = new FormatSeparator();
for (String[] s : tempList) {
if (counter < 6) {
tempMap.put(s[1], Double.parseDouble(s[3]));
counter++;
} else if (counter++ > 6 && counter < 18) {
Double tempDouble = 0d;
for (int i = 0; i < s.length; i++) {
if (i == 0) {
tempDouble += Double.parseDouble(s[i])* tempMap.get(fs.formatSeparator(s[i + 1]));
} else if (((i - 2) % 3) == 0) {
if (s[i].equals("+")) {
tempDouble += Double.parseDouble(s[i + 1])* tempMap.get(fs.formatSeparator(s[i + 2]));
} else if (s[i].equals("-")) {
tempDouble -= Double.parseDouble(s[i + 1])* tempMap.get(fs.formatSeparator(s[i + 2]));
}
}
}
doubleList.add(tempDouble);
}
}
br.close();
reader.close();
// write string to file
FileWriter writer = new FileWriter(System.getProperty("user.dir")
+ File.separator + "output.txt");
BufferedWriter bw = new BufferedWriter(writer);
DecimalFormat df = new DecimalFormat("0.00");
String crlf = System.getProperty("line.separator");
bw.write("e-mail address");
bw.write(crlf + "");
for (Double d : doubleList) {
bw.write(crlf + df.format(d) + " m");
}
bw.close();
writer.close();
} catch (FileNotFoundException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
}
}
package com.github.alaahong;
public class FormatSeparator {
public String formatSeparator(String measure) throws FormatException {
switch (measure) {
case "mile":
measure = "mile";
break;
case "miles":
measure = "mile";
break;
case "yard":
measure = "yard";
break;
case "yards":
measure = "yard";
break;
case "inch":
measure = "inch";
break;
case "inches":
measure = "inch";
break;
case "foot":
measure = "foot";
break;
case "feet":
measure = "foot";
break;
case "fath":
measure = "fath";
break;
case "faths":
measure = "fath";
break;
case "furlong":
measure = "furlong";
break;
case "furlongs":
measure = "furlong";
break;
case "m":
measure = "m";
break;
case "meters":
measure = "m";
break;
default:
throw new FormatException(measure);
}
return measure;
}
public class FormatException extends Exception {
/**
* define my exception
*/
private static final long serialVersionUID = 1L;
public FormatException() {
super();
System.out.println("Formating Error!");
}
public FormatException(String msg) {
super(msg);
System.out.println("Formating Error!");
}
}
}
钱总最近写脚本比较多，他用的ruby
class Length
def initialize
@map = Hash.new
@result = Array.new(10,0)
@count = 0
end
def map
@map
end
def setFile(fn = "input.txt")
@file = fn
end
def readFile()
File.open(@file,"r") do |file|
while line=file.gets
if match = /\s*\d+\s*(\w+)\s*=\s*(\d+.\d*)\s*m\s*/.match(line)
@map[match[1]] = match[2].to_f
elsif line.lstrip!=""
calculate(toSingle(line),@count)
@count += 1
end
end
end
end
#把复数变成单数
def toSingle(str)
str = str.gsub(/miles/,"mile")
str = str.gsub(/inches/,"inch")
str = str.gsub(/feet/,"foot")
str = str.gsub(/yards/,"yard")
str = str.gsub(/faths/,"fath")
end
#转化成米为单位
def transfer(str)
if match = /\s*(\d+(.\d+){0,1})\s*(\w+)/.match(str)
return match[1].to_f * @map[match[3]]
end
end
#计算表达式
def calculate(str,n)
if match = /(\s*\d+(.\d+){0,1}\s*\w+)((\s*([+-])\s*\d+(.\d+){0,1}\s*\w+)*)/.match(str)
@result[n] += transfer(match[1])
end
if match[3].to_s.lstrip != ""
substr = match[3]
while subMatch = /(([+-])\s*\d+(.\d+){0,1}\s*\w+)(\s*[+-][\d\w\s.]+)*/.match(substr)
if subMatch[2] == "+"
@result[n] += transfer(subMatch[1])
elsif subMatch[2] == "-"
@result[n] -= transfer(subMatch[1])
end
if subMatch[4].to_s.lstrip != ""
substr = subMatch[4]
else
break
end
end
end
end
#保留两位小数
def doFormat
10.times do |i|
@result[i] = format("%.2f",@result[i])
end
end
#写入文件
def appendFile
f = File.new("output.txt","w") #覆盖---w 追加---a
f.puts("e-mail address")
f.puts
10.times do |i|
f.puts(@result[i].to_s + " m" )
end
f.close
end
end
f = Length.new
f.setFile
f.readFile
f.doFormat
f.appendFile
本来以为鑫磊会按比赛的习惯去写C++的，没想到用php了
<?php
$file = file_get_contents('input.txt');
$out = explode("\n", $file);
$out_val = array();
$file = fopen("output.txt","a");
fwrite($file,"e-mail address\r\n");
fwrite($file,"\r\n");
foreach($out as $key => $value)
{
$val = explode(' ', $value);
if(count($val) == 1) continue;
if(in_array('=', $val))
{
if($val[1] == 'mile')
{
$out_val['miles'] = $val[3];
$out_val['mile'] = $val[3];
}
else if($val[1] == 'yard')
{
$out_val['yard'] = $val[3];
$out_val['yards'] = $val[3];
}
else if($val[1] == 'inch')
{
$out_val['inch'] = $val[3];
$out_val['inches'] = $val[3];
}
else if($val[1] == 'foot')
{
$out_val['foot'] = $val[3];
$out_val['feet'] = $val[3];
}
else if($val[1] == 'fath')
{
$out_val['fath'] = $val[3];
$out_val['faths'] = $val[3];
}
else if($val[1] == 'furlong')
{
$out_val['furlong'] = $val[3];
}
}
else if(in_array('+', $val) || in_array('-', $val))
{
$j = trim($val[1]);
$sum = $out_val[$j]*$val[0];
for($i = 1; $i <= (count($val)-2)/3; $i++)
{
$j = $val[$i*3+1];
$j = trim($j);
$ret = $out_val[$j]*$val[$i*3];
if($val[$i*3-1] == '+')
{
$sum = $sum+$ret;
}
else
{
$sum = $sum-$ret;
}
}
$sum = sprintf("%.2f",$sum);
fwrite($file,"$sum m\r\n");
}
else
{
$j = trim($val[1]);
$sum = $out_val[$j]*$val[0];
$sum = sprintf("%.2f",$sum);
fwrite($file,"$sum m\r\n");
}
}
fclose($file);
?>
几个人不见，大家风格变化不少...