could someone explain this line to me please

Okay I normally program in c++ but the book I use to learn win32 is written in c. I've come across a couple of line that i don't understand, can someone please explain these to me.
The first one is:

Code:

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int iLength;
TCHAR szBuffer[40];
iLength = (szBuffer, TEXT("The sum of %i and %i is %i"),  //i really don't get the %i part
                  iA, iB, iA + iB);
TextOut(hdc, x, y, szBuffer, iLength);

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basically the only one that gets me is the i length = statment.

The other one is

Code:

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wsprintf(szBuffer, TEXT("%5d"),  //i don't get the %5d part

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Thanks for any help.

%i just signafies that a variable is in the place of the %, so %d means an integer, so if you wanted to output to the screen someones name and age from variables you would do something like:

printf("Your name is: %s and your ages is %d",name,age);
so all your text goes inside "" and then after that you put all the variables that you used from left to right seperating them with commas.

Allright that pretty much clears things up. THanks a bunch.