--
#includei<stream.h>
#include<conio.h>
#include<fstream.h>
#include<stdlib.h>
#include<ctype.h>
void main()
{
char fname[20];
ifstream fin; ofstream fc,fu,fl,fd;
cout<<"\n Enter file name : ";
cin>>fname;
fin.open(fname,ios::in);
fc.open("convert.txt",ios::out);
fu.open("upper.txt",ios::out);
fl.open("lower.txt",ios::out);
fd.open("digit.txt",ios::out);
if(fin.fail())
{
cout<<"file not exists ";
exit(1);
}
char ch;
while(!fin.eof())
{
ch=fin.get();
if(islower(ch))
{
fl.put(ch);
ch=toupper(ch);
fc.put(ch);
}
else if(isupper(ch))
{
fu.put(ch);
ch=tolower(ch);
fc.put(ch);
}
else if(isdigit(ch))
{
fd.put(ch);
}
else if(isspace(ch))
{
fc.put(ch);
}
}
cout<<"file coped....";
getch();
}