C++怎么处理同一文件夹里多个txt文件

#include "stdafx.h"
#include <fstream>
#include<iostream>
#include<iomanip>
#include<cstring>
#include<cstdlib>
using namespace std;
int main()
{
//ofstream cout("C:\\Users\\Administrator\\Desktop\\GM.txt", ios::out);///输出

char c;
int line = 1;
fstream fin1("11111.txt", ios::in);
if (!fin1)
{
cerr << "不能打开文件" << endl;
system("pause");
return -1;
}
cout << "读取成功！" << endl;

while (fin1.get(c))
{
if (c == '\n')
line++;
}
cout << "txt文本一共" << line << "行！" << endl;
//txt文件最后一定不能有空白行，否则行数错误！！！

ifstream fileinput;

fileinput.open("C:\\11111.txt");

double **data;
data = new double*[line];
for (int i = 0; i < line + 1; ++i)
{
data[i] = new double[10];
}

//多建立了一行一列 否则Run-Time Check Failure #2 - Stack around the variable 'fileinput' was corrupted.

for (long i = 1; i <= line + 1; i++)
{

for (int j = 1; j <= 9; j++)

{

fileinput >> data[i][j];

}

}
fileinput.close();
ofstream write;
write.open("text.txt");
cout << "股票名称" << data[1][1] << endl;
write << "股票名称" << data[1][1] << endl;

//用来计算收盘价格之和
double a = 0;
for (int b = 2; b <= 244; b++)
{
a += data[b][7];
}
cout << std::fixed << setprecision(2) <<"收盘价格之和"<< a << '\n' << endl;
write << std::fixed << setprecision(2) << "收盘价格之和" << a << '\n' << endl;
//用来设置量比的大小
double ratio;
cout << "请设置量比的值：";
write << "请设置量比的值：";
cin >> ratio;
write << ratio << endl;
//下一段函数用来求每5天的成交量的均值

double aver[240];

for (int d = 1; d <= 239; d++)
{
aver[d] = (data[d + 1][8] + data[d + 2][8] + data[d + 3][8] + data[d + 4][8] + data[d + 5][8]) / 5;
}
//验证平均值是否正确，可以不用输出
for (int i = 1; i <= 239; i++)
{
cout << "成交量第" << i << "天到第" << i + 4 << "天的平均值如下：" << aver[i] << endl;
}
//判断是否放量，并输出日期

int total = 0;
for (int today = 7; today <= 244; today++)
{
if (data[today][8] / aver[today - 6] >= ratio)
{
total++;
cout << std::fixed << setprecision(0) << "日期:" << data[today][1] << "/" << data[today][2] << "/" << data[today][3]
<< "放量了" << endl;
write << std::fixed << setprecision(0) << "日期:" << data[today][1] << "/" << data[today][2] << "/" << data[today][3]
<< "放量了" << endl;
}
}
cout << "一共" << total << "天放量了！" << endl;
write << "一共" << total << "天放量了！" << endl;

write.close();

system("pause");
return 0;

}
我的意思是处理完11111.txt这个文件后，让程序自动继续执行下一个txt文件，不用修改程序