using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Text;
using System.Text.RegularExpressions;
using System.Threading.Tasks;

using System.Collections;
namespace ConsoleApplication1
{
class v
{

public int n { get; set; }
public string s { get; set; }
public v(int nu, string st)
{
this.n = nu;
this.s = st;
}

}
class Program
{
static void Main(string[] args)
{
if (args.Length ==1)
{
Dictionary<string, v> ht = new Dictionary<string, v>();

if (args.Length == 0)
{
Console.WriteLine("please input the correct file adress");
}
string path = args[0];

if (!Directory.Exists(path))
{
Console.WriteLine("wrong path");
}
else
{
if ((Directory.GetFiles(path).Length == 0) && (Directory.GetDirectories(path).Length == 0))
Console.WriteLine("empty directory");
else
{

string[] file = (Directory.GetFiles(path, "*", SearchOption.AllDirectories)).Where(s => s.EndsWith(".txt") || s.EndsWith(".h") || s.EndsWith(".cpp") || s.EndsWith(".cs")).ToArray();
int l = file.Length;
for (int i = 0; i < l; i++)
{
string s = "(\\b[a-zA-Z]{3}[A-Za-z0-9]+)|(\\b[a-zA-Z]{3})|((_[a-zA-Z]{3}[A-Za-z0-9]+)|(_[a-zA-Z]{3}))";
string article = File.ReadAllText(file[i]);
foreach (Match m in Regex.Matches(article, s))
{
string c = m.ToString();
if (c.Contains("_"))
{
c = c.Replace("_", "");
}
string n = c.ToLower();
if (ht.ContainsKey(n))
{
v w = (v)ht[n];
if (c.CompareTo(w.s) >= 0)
{
w.n += 1;
w.s = c;
}
else
w.n += 1;
}
else
{
v w = new v(1, c);
ht.Add(n, w);
}
}
}

}
}
var re = ht.OrderByDescending(v => v.Value.n).ThenBy(v => v.Value.s);
StreamWriter sw = new StreamWriter(path + "\\黄敬博.txt", false);
foreach (var skey in re)
{

v w = (v)ht[skey.Key];
sw.WriteLine(w.s + "\t" + w.n);

}
sw.Flush();

}
if (args[0].Equals("-e2"))
{
int j = 1;
Dictionary<string, v> ht = new Dictionary<string, v>();
if (args.Length == 0)
{
Console.WriteLine("please input the correct file adress");
}
string path = args[1];
if (!Directory.Exists(path))
{
Console.WriteLine("wrong path");
}
else
{
if ((Directory.GetFiles(path).Length == 0) && (Directory.GetDirectories(path).Length == 0))
Console.WriteLine("empty directory");
else
{

string[] file = (Directory.GetFiles(path, "*", SearchOption.AllDirectories)).Where(s => s.EndsWith(".txt") || s.EndsWith(".h") || s.EndsWith(".cpp") || s.EndsWith(".cs")).ToArray();
int l = file.Length;
for (int i = 0; i < l; i++)
{
string s = @"\b[A-Za-z]{3,}[A-Za-z0-9]*\s{1}\b[A-Za-z]{3,}[A-Za-z0-9]*";
string article = File.ReadAllText(file[i]);
Regex reg = new Regex(s);
Match m = reg.Match(article, 0);
while (m.Success)
{

String word = m.ToString();
string n = word.ToLower();
if (ht.ContainsKey(n))
{
v w = (v)ht[n];
if (word.CompareTo(w.s) >= 0)
{
w.n += 1;
w.s = word;
}
else
w.n += 1;
}
else
{
v w = new v(1, word);
ht.Add(n, w);
}
m = reg.Match(article, m.Index + m.ToString().IndexOf(‘ ‘));
}

}

}
}
var re = ht.OrderByDescending(v => v.Value.n).ThenBy(v => v.Value.s);
StreamWriter sw = new StreamWriter(path + "\\黄敬博.txt", false);
foreach (var skey in re)
{

v w = (v)ht[skey.Key];
sw.WriteLine(w.s + "\t" + w.n);
sw.Flush();
j++;
if (j > 10)
break;
}
}
if (args[0].Equals("-e3") )
{
int j = 1;
Dictionary<string, v> ht = new Dictionary<string, v>();
if (args.Length == 0)
{
Console.WriteLine("please input the correct file adress");
}
string path = args[1];
if (!Directory.Exists(path))
{
Console.WriteLine("wrong path");
}
else
{
if ((Directory.GetFiles(path).Length == 0) && (Directory.GetDirectories(path).Length == 0))
Console.WriteLine("empty directory");
else
{

string[] file = (Directory.GetFiles(path, "*", SearchOption.AllDirectories)).Where(s => s.EndsWith(".txt") || s.EndsWith(".h") || s.EndsWith(".cpp") || s.EndsWith(".cs")).ToArray();
int l = file.Length;
for (int i = 0; i < l; i++)
{
string s = @"\b[A-Za-z]{3,}[A-Za-z0-9]*\s{1}\b[A-Za-z]{3,}[A-Za-z0-9]*\s{1}\b[A-Za-z]{3,}[A-Za-z0-9]*";
string article = File.ReadAllText(file[i]);
Regex reg = new Regex(s);
Match m = reg.Match(article, 0);
while (m.Success)
{

String word = m.ToString();
string n = word.ToLower();
if (ht.ContainsKey(n))
{
v w = (v)ht[n];
if (word.CompareTo(w.s) >= 0)
{
w.n += 1;
w.s = word;
}
else
w.n += 1;
}
else
{
v w = new v(1, word);
ht.Add(n, w);
}
m = reg.Match(article, m.Index + m.ToString().IndexOf(‘ ‘));
}

}

}
}
var re = ht.OrderByDescending(v => v.Value.n).ThenBy(v => v.Value.s);
StreamWriter sw = new StreamWriter(path+"\\黄敬博.txt", false);

foreach (var skey in re)
{

v w = (v)ht[skey.Key];
sw.WriteLine(w.s + "\t" + w.n);
sw.Flush();
j++;
if (j > 10)
break;
}
}
}
}
}

代码总共由3部分组成，每部分对应相对的mode。

mode2、3是基于mode1基础上做出的一点点改变。

这个程序主要利用了Dictionary功能。key设为string，使用时将单词的小写形式作为key。value设为一个小结构，包含一个string类型的单词和一个int类型的次数。

mode1遍历的过程为按照单个单词遍历的，mode2为两个，mode3为三个。

但mode2读取完两个单词需要往回退一个，mode3读取完要往回退两个。

若读取的单词的小写形式在dictionary中已经包含了。则value中的int值+1，然后比较value中的string与当前的单词，选择ASC码靠前的那个保存。

最后按照要求输出。

Individual Project - Word frequency program by HJB