how to convert the upper case letter to lower case as if i enter "KHUSHAL"
the output it gives is "khushal" and same as i enter "khushal" it gives "KHUSHAL".please explain it by sending the code but complete code.

See function tolower().

sir i need my own code to write about converting the code i dont want to use the already made library functions please help me sir

If your intention is to learn to be a professional programmer, you will need to learn:

• how to use a search engine to find your own answers.
• how to look at problems long enough to see & understand the patterns contained.

...but I will give you a hint: look at an ASCII table. See that the sequences A-Z & a-z always increase:

• 'A' + 1 = 'B'
• 'B' + 1 = 'C'
• ...

...& correspondingly,

• 'a' + 1 = 'b'
• 'b' + 1 = 'c'
• ...

Now try to determine whether there is a relationship between 'A' and 'a'. In other words, determine whether there is a constant which can be added to the ASCII code for 'A' which will produce 'a'. See if this same relationship holds for 'B'. etc. Once you see a pattern, figure out whether you can write C++ code which will automate the decisions you just made.

One of the biggest skills used in programming is learning how to look at problems inductively.

You will also need to learn how to try things out on your own without just asking for answers. You'll be amazed at how much you will learn when you attempt to create a program.

If your goal is not to learn how to program then, like I said before, please send $125.00 US. Thanks.