loading large file into buffer

ifstream file1 ("1.txt", ios::in|ios::binary|ios::ate);
ifstream file2 ("2.txt", ios::in|ios::binary|ios::ate);
b1size = file1.tellg();
b2size = file2.tellg();
file1.seekg (0, ios::beg);
file2.seekg (0, ios::beg);
buffer1 = new char [b1size];
buffer2 = new char [b2size];
file1.read (buffer1, b1size);
file2.read (buffer2, b2size);
file1.close();
file2.close();
//cout << "the complete file is in a buffer";
fo.open("out.txt",ios::out);
for (i=0;i<b1size;i++)
//fo <<buffer1[i]<<"\t"<<"*"<<"\t"<<buffer2[i]<<"\t"<<"="<<"\t"<< buffer1[i]*buffer2[i]<<"\t";
fo <<buffer1[i]*buffer2[i]<<"\t";
fo.close();
delete[] buffer1;
delete[] buffer2;

by the above code i am handling 2 large file(1.txt and 2.txt) is both of 109 mb.i m trying to element by elemnet multiplication of the both file.but when i am loading both file into buffer its not a wise way.so i need to do it by taking one elements from both file and manipulate(*) it and then delete the buffer to load to load anoter element to manipulate.

plz send me by changing my code.

Please use code tags.

Actually you are multiplying each byte of 1.txt with each byte of 2.txt, maybe you want to multiply 4 byte integers, instead of 1 byte integers.

This code use streaming.

Code:

---

#include <fstream>

using std::ios;
using std::char_traits;

int main()
{
std::ifstream file1("1.txt",ios::in|ios::binary);
std::ifstream file2("2.txt", ios::in|ios::binary);
std::ofstream ofile("out.txt",ios::out|ios::binary|ios::trunc);

char c1,c2;
while(file1.get(c1).good() && file2.get(c2).good())
        {
        ofile.put(c1*c2);
        }
ofile.close();
file2.close();
file1.close();

return 0;
}

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Be aware, though, that there is a good chance that the product of 2 char values won't fit into a single char variable...