Help with file Streams

I need to make this program write to a file and read it. I have got the writing part down but when it tries to read and display the information i get wierd numbers can anyone tell me whats wrong?

#include <iostream.h>
#include <fstream.h>
#include <iomanip.h>
#include <stdlib.h>


int main()

{
int num;
int counter=0;
int enter;

ofstream outstream("digits2.dat");

if(outstream.fail())
{
cout<<"File Problem"<<endl;
exit(1);
}

for(counter=0; counter<5; counter++)
{
outstream<<1;

outstream<<2;

outstream<<3;
}


outstream.close();







ifstream instream("digits2.dat"); //opens files for reading



if (instream.fail() )
{
cout<<"File problem!"<<endl;
exit(1); //stop execution
}



while (instream>>num)
{

for(counter=0; counter<5; counter++)
{
cout<<num;
}


counter++;
outstream<<num;
cout<<num<<" ";
}

cout<<num<<endl;

cout<<"There were "<<counter<<" numbers read"<<endl;



instream.close();

cout<<"\n\n Program finished";
cin>>enter;
return(0);

}

ell to find a string within a line read from a file, do something like this...
#include <stdio.h>
#include <string.h>

int main ( ) {
char buff[BUFSIZ];
FILE *fp = fopen("keywords.txt","r");
while ( fgets( buff, BUFSIZ, fp ) != NULL ) {
if ( strstr(buff,"word") != NULL ) {
printf( "%s", buff );
}
}
fclose( fp );
return 0;
}

have you opened digits2.dat to see what's in it? Maybe you have a problem writing to the file, not reading from it.

You may need to make a call to clear() after the call to fail(). I generally use the syntax: if(!outstream)

After the first half of your program you close the ofstream. But then you use it again in the second half of the program without reopening it.

outstream << 2; might not put anything in the file. to print 2 to the file try this outstream << "2"; or outstream << '2';