#include <iostream>
#include <fstream>
#include <stdlib.h>
#include <windows.h>
#include <cstdlib>   
#include <time.h>
#include <sstream>    // needed to convert int to string
using namespace std;

const int LOW = 1;
const int HIGH = 1000;

void randomfilename(string a, string b, string c, string d, string e)
{
     
    time_t seconds;
    time(&seconds);
    srand((unsigned int) seconds);
   
    int random = rand() % (HIGH - LOW + 1) + LOW;
   
    string s;
    std::stringstream out;
    out << random;
    s = out.str();
   
    ofstream goods;
    goods.open(a+s+".txt");
    goods<<random;
    goods.close();
}

int main()
{
    randomfilename("hi","hi","hi","hi","hi");
    return 0;
}

Compiler: Default compiler
Building Makefile: "C:\Documents and Settings\Owner\Desktop\Programing\c++\VIRUSES\360 mod\Makefile.win"
Executing  make...
make.exe -f "C:\Documents and Settings\Owner\Desktop\Programing\c++\VIRUSES\360 mod\Makefile.win" all
g++.exe -c main.cpp -o main.o -I"C:/Dev-Cpp/lib/gcc/mingw32/3.4.2/include"  -I"C:/Dev-Cpp/include/c++/3.4.2/backward"  -I"C:/Dev-Cpp/include/c++/3.4.2/mingw32"  -I"C:/Dev-Cpp/include/c++/3.4.2"  -I"C:/Dev-Cpp/include"   

main.cpp: In function `void randomfilename(std::string, std::string, std::string, std::string, std::string)':
main.cpp:36: error: no matching function for call to `std::basic_ofstream<char, std::char_traits<char> >::open(std::basic_string<char, std::char_traits<char>, std::allocator<char> >)'
C:/Dev-Cpp/include/c++/3.4.2/fstream:695: note: candidates are: void std::basic_ofstream<_CharT, _Traits>::open(const char*, std::_Ios_Openmode) [with _CharT = char, _Traits = std::char_traits<char>]

make.exe: *** [main.o] Error 1

Execution terminated

#include <fstream>
#include <time.h>
#include <stdlib.h>
#include <string>
using namespace std;

int main()
{
  int namelength = 10;
  char buf[2] = {0, 0};
  string name;

  srand((int)time(0));

  for (int x = 0; x < namelength; ++x)
  {
    buf[0] = 'a' + rand() % 26;
    name += buf;
  }

  name += ".txt";

  ofstream fout(name.c_str());

  if (fout.good())
    fout.close();

  return 0;
}