I din ask for ACTUAL answer, ok ?
I din ask you guy to help me do entire program, i only got ONE question !
I only wish to know, can i use the functions : strlen, strrev, etc
Since the question there say "not allowed to use any functions in the <string.h> library."
Please, only answer me CAN or NOT

Develop a program that allows the user to enter a string and performing the following operations on it:
- Count Number of Characters In String
- Count Number of Words In String
- Remove Spaces In String
- Reverse String
- Reverse Words In String
- Look For Substring In String
- Insert Substring Into String

The following screen suggests a possible user interface:

Enter String: C is Fun!

1 ¡V Count Number of Characters In String
2 - Count Number of Words In String
3 - Remove Spaces In String
4 ¡V Reverse String
5 ¡V Reverse Words In String
6 ¡V Look For Substring In String
7 ¡V Insert Substring Into String

Enter Choice:


whereby:

If option 1 is chosen, 7 (including any special characters but excluding spaces) is shown on the screen.
If option 2 is chosen, 3 is shown on the screen
If option 3 is chosen, 'CisFun!' is shown on the screen
If option 4 is chosen, '!nuF si C' is shown on the screen
If option 5 is chosen, 'C si !nunF' is shown on the screen
If option 6 is chosen, get user to enter the substring he wants to find and display a message to tell him whether it is in the string
If option 7 is chosen, get user to enter a substring, and the position he wants to insert into the original string. The new string is then displayed on the screen.
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