C/C++ :: Program To Copy A File From Source And Paste With Different Name

I have written a program that copies a file from the source and pastes it there (same location), but with a different name. The program works fine, except there is a small bug that i can't seem to fix. Here is the code:

/*
This program copies a file from the current directory and pastes it to the same directory, but with a different name. The file name form the source must include the extension as well.
*/

#include <stdio.h>
#include <conio.h>
#include <stdlib.h>
int main() {
char temp, s_file[100], d_file[100],

[Code] ....

This is the flow:

> 1) Enter the name of the file you'd like to copy (Must be from the current directory)
> A: 3.c // This depends if the file exists in the
> current directory
>
> 2) Enter the name of the destination file (The file will be copied to the same directory)
> A: 4 //The extension isn't necessary here
>
> Result: The file was copied successfully!

When I run the prg again, and this time input a file name with no extension, like this:

> Enter the name of the file you'd like to copy (Must be from the current directory)
> 3
> You did not enter a valid text. Press "?" to get help or "x" to exit.

I hit "?" and it takes me to

> 1. The file must be from the current directory)
> 2. The location mustn't be empty

Then it asks me

> Try again? (Y/N)

If i give N, it exits. BUT if I give Y, it goes, like this:

> Enter the name of the file you'd like to copy (Must be from the current directory)
> You did not enter a valid text. Press "?" to get help or "x" to exit.

You see, it doesn't give me the option to give it the file name..