文件处理

在做软件度量作业的过程中，遇到了文件中上千条记录的处理。程序如下：

C++的读文件

字符串取子串等

#include <iostream>
#include <map>
#include <fstream>
#include <string>
using namespace std;

int main()
{
    fstream fin;
    string filename = "E:\002Validate Binary Search Tree\Debug\bugs-2013-11-30.csv";
    fin.open(filename);
    if(fin.bad())
    {
        cout<<"文件打开失败"<<endl;
        return 0;
    }
    string line;
    int first,last;
    string changeddata;
    map<string,int> count;
     
    while(!fin.eof())
    {
        std::getline(fin,line);
        int comma = line.find_last_of(',');
        first = line.find_first_of('//',comma+1);
        last = line.find_first_of('//',first+1);
        if(first!=-1 && last!= -1)
        {
            if(first<5||last-first<1)
                continue;
            changeddata = line.substr(first-4,last-first+4);

            if(count.find(changeddata)==count.end())
                count.insert(pair<string,int>(changeddata,1));
            else
                count[changeddata] +=1;

        }
    }
    for(map<string,int>::iterator iter = count.begin();iter!=count.end();iter++)
    {
        //cout<< iter->first <<"  "<< iter->second<<endl;
        //cout<< iter->first<<endl;
        cout<<iter->second<<endl;
    }
    return 0;
}