统计一个文件英文单词的个数

/*
	统计一个文件内。英文单词的个数，并按 word = count的格式顺序输出	
	统计输出总的英文单词个数
*/

#include <fstream>
#include <iostream>
#include <string>
#include <vector>
#include <algorithm>
using namespace std;
int main(){
	string line;
	//打开输入文件
	ifstream input("transform.txt");
	//打开输出文件
	ofstream output("result.txt");
	//使用两个vector来实现map的功能，差别是按顺序统计单词，而不是按键值
	vector<string> wordVec;
	vector<int> countVec(200);
	//单词计数
	int wordCount=0;
	//每次读一行
	while(getline(input,line))
	{	
		size_t pos=0;
		//先按空格切割字符串
		while(pos!=line.size()){
			if(line[pos]!=' '){
				string word;
				while(pos!=line.size() && line[pos]!=' '){
					word+=line[pos];
					++pos;
				}
				
				//去掉子字符串的前导标点符号
				int prepos=0;
				while(prepos!=word.size() && ispunct(word[prepos])){
					++prepos;
				}
			
				//去掉子字符串的后缀标点符号
				//注意无符号数和有符号数
				int pofixPos=word.size()-1;
				while((pofixPos>=0) && ispunct(word[pofixPos])){
					--pofixPos;
				}
			
				//跳过无效单词的统计操作
				if(prepos==word.size() || pofixPos<0)
					continue;
				else
					++wordCount;
				//得到处理后的单词，统计单词个数
				string pureWord=word.substr(prepos,pofixPos-prepos+1);
				vector<string>::iterator iter=find(wordVec.begin(),wordVec.end(),word);
				if(iter==wordVec.end()){
					countVec[iter-wordVec.begin()]++;
					wordVec.push_back(pureWord);
				}else
					countVec[iter-wordVec.begin()]++;
				if(pos==line.size())
					break;			
			}
			++pos;		
		}
	}
	//关闭输入文件
	input.close();
	//遍历得的单词统计的具体结果
	vector<string>::iterator traiter=wordVec.begin();
	vector<int>::iterator coniter=countVec.begin();
	output<<"单词总数 ："<<wordCount<<endl;
	while(traiter!=wordVec.end()){
		output<<*traiter<<" = "<<*coniter<<endl;
		++traiter;
		++coniter;
	}
	//关闭输出文件
	output.close();
	return 0;
}

输入文件transform.txt内容：

My father was a self-taught mandolin player. He was one of the best string instrument players in our town. 
He could't read music, but if he heard a tune a few times, he could play it. When he was younger, he was a member of a small country music band. 
They would play at local dances and on a few occasions would play for the local radio station. 
He often told us how he had auditioned and earned a position in a band that featured Patsy Cline as their lead singer.

输出文件result.txt内容：

单词总数 ：91
My = 1
father = 1
was = 4
a = 8
self-taught = 1
mandolin = 1
player = 1
He = 3
one = 1
of = 2
the = 2
best = 1
string = 1
instrument = 1
players = 1
in = 2
our = 1
town = 1
could't = 1
read = 1
music = 2
but = 1
if = 1
he = 5
heard = 1
tune = 1
few = 2
times = 1
could = 1
play = 3
it = 1
When = 1
younger = 1
member = 1
small = 1
country = 1
band = 2
They = 1
would = 2
at = 1
local = 2
dances = 1
and = 2
on = 1
occasions = 1
for = 1
radio = 1
station = 1
often = 1
told = 1
us = 1
how = 1
had = 1
auditioned = 1
earned = 1
position = 1
that = 1
featured = 1
Patsy = 1
Cline = 1
as = 1
their = 1
lead = 1
singer = 1