ASCII

ASCII codes

As a high level programmer we see our laptop keyboard 

as a bunch of keys with character printed on them

& some special keys like ,

that key with windows logo

alt key, ctrl key, num-lock etc

using ASCII codes, 

we  encode all of this character

i.e., we assign a bit pattern to each of these character

e.g. for 

alphabetic character  'A' ≣  65(in decimal)  ≣  1000001(in binary)

space        character   '  '  ≣ 32(in decimal)  ≣  0100000(in binary)

Now let's run a C++ pgm that prints 'A'

there are two alternatives, 

we directly initialize a character with 'A'

or we can initialize character with 65

#include<bits/stdc++.h>

using namespace std;

int main(){

    char c1 = 'A';

    char c2 = 65;

    cout << c1 ;

    cout << c2;

    return 0;

}

g++ --version                // to chk g++ version installed in your windows10 PC

g++ -g code.cpp -o code.exe  // to compile code

// after compiling code a binary file code.exe is created

code.exe                      // running executable file

C++ pgm to produce alert sound

there are non printable characters (or whitespace character)

like '\n'           :               to print newline character

like '\t'            :               to print tab

similarly we have '\a' : to produce alert sound 

#include<bits/stdc++.h>

using namespace std;

int main(){

    cout << '\a';

    return 0;

}

you can how it sounds when we run the program 

It's a alert sound

Similarly we have other whitespace or special character.

For more interesting codes like Unicode currently

you can refer here