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What is this "%" doing in this code and what is it called and used for in C++?

#include <stdio.h>
4:  main()
5:  {
6:     char  c, *ptr_c;
7:     int   x, *ptr_x;
8:     float y, *ptr_y;
10:    c = 'A';
11:    x = 7;
12:    y = 123.45;
13:    printf("c: address=%p, content=%c\n", &c, c);
14:    printf("x: address=%p, content=%d\n", &x, x);
15:    printf("y: address=%p, content=%5.2f\n", &y, y);
16:    ptr_c = &c;
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1 Solution
The % tells the shell how to interpret the item in the variable argument list:
%c means character
%d means digit (integer)
%f means floating point.
Sorry, there's more.  The %5.2f means show 5 characters with 2 decimal places, and the %p means address.
Sorry, I keep doing this too fast.  They are format specifiers, and tell the compiler how to display characters.  C++ has shyed away from this a bit, preferring streams (this is from C), but there still are many times when this is more convenient.
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awjackin35Author Commented:
So where can I find th format specifiers? Are they in the header file?
It is standatd format specification for the pronting out the variables of various types in various form. This used in printf(), sprintf()  C-functions.

In the first line, f.e.

printf("c: address=%p, content=%c\n", &c, c);

instead of %p will be printed the address of c variable,
instead of %c - its value.
So, %p means the address formar type, %c - the cahracter format type.
%d means the decimal integer number format,
%f is the floating point number format. %5.2f in your
code means that it will print the floating variable y, resting only first 2 digits after the point and the total width (number of digits, including the point) of your number is 5.

For more information see the microsoft site below.
It called a modular. it is used in this case as a pointer reference. it formats the value to be out putted.
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Hi (awjackin35):
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awjackin35Author Commented:
The answer was acceptable but I have to follow the rules.
awjackin35Author Commented:
HI mnashadka
    Your answer was ver informative to me and thanks!!!!!!!

Mr. Hakob
     Your answer was very good as well but I made the same mistake on the Vb forum and so since they are very critical of the protocal on the forums I have to follow the rules.

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