C++统计单词小程序

#include <fstream>

#include <string>

#include <iostream>

#include <map>

using namespace std;



int main()

{

	string str;

	ifstream infile;

	ofstream outfile;

	map<string,int> wordCount;

	map<string,int>::iterator iter;



	infile.open("in.txt");

	outfile.open("out.txt");

	//测试输入文件是否打开

	if (!infile)

	{

		cerr<<"error:unable to open input file:"

			<<infile<<endl;

		return -1;

	}

	while(infile>>str)

	{

		wordCount[str]++;//统计单词出现次数

	}

	for (iter=wordCount.begin();iter!=wordCount.end();++iter)

	{

		cout<<iter->first<<":"<<wordCount[iter->first]<<endl;//标准输出

		outfile<<iter->first<<":"<<wordCount[iter->first]<<endl;//输出到文件

	}

	infile.close();

	outfile.close();

	return 0;

}