import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;

public class pliki {

public static void main(String[] args) throws IOException {
plik1();
plik2();

}

public static void plik1(){
File plik=new File("F:\\1.txt");
try {
plik.createNewFile();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}

public static void plik2() throws IOException{
FileOutputStream out=new FileOutputStream("F:\\2.txt",true);
for(int i=10;i<=100;i++){
out.write(i);
}

FileInputStream in=new FileInputStream("F:\\3.txt");
while(true){
int x=in.read();
if(x==-1){break;}
System.out.print(x);
}

}

}