play_with_pointers_v1.c

/*

    play_with_pointers_v1.c

    Useful link for ASCII table
    http://www.asciitable.com/


    You can find all my C programs at Dragan Milicev's pastebin:

    https://pastebin.com/u/dmilicev

*/


#include <stdio.h>

int main()
{
    char *str = "GATEEXAM";

    printf("\n str = %s \n\n", str );
    printf("\n ---------------------- \n");

    printf("\n *((str--)   )  )   = %c \n", *((str--    )  )  ); // G
    str++;  // because we had str--
    printf("\n *((str-- + 2)  )   = %c \n", *((str-- + 2)  )  ); // T
    str++;  // because we had str--
    printf("\n *((str-- + 2)+1)   = %c \n", *((str-- + 2)+1)  ); // E
    str++;  // because we had str--
    printf("\n *((str-- + 2)+1)-3 = %c \n", *((str-- + 2)+1)-3); // B because E-3=B in ASCII table
    str++;  // because we had str--

    printf("\n ---------------------- \n");

    printf("\n *(--str  )    = %c \n", *(--str  )    ); // something in memory, left from G, undefined
    str++;  // because we had str--
    printf("\n *(--str+3)    = %c \n", *(--str+3)    );  // T
    str++;  // because we had str--
    printf("\n *(--str+3)+32 = %c \n", *(--str+3)+32 );  // t because T+32=t in ASCII table
    str++;  // because we had str--

    printf("\n ---------------------- \n");

    printf("\n *(++str  )   = %c \n", *(++str  )   );  // A
    --str;  // because we had ++str
    printf("\n *(++str+2)   = %c \n", *(++str+2)   );  // E
    --str;  // because we had ++str
    printf("\n *(++str+2)+4 = %c \n", *(++str+2)+4 );  // I because E+4=I in ASCII table
    --str;  // because we had ++str

    printf("\n ---------------------- \n");


    return 0;
}