/**Solution to exercise 5.8, p. 199, "C by Dissection"
 *
 * 
 * Prints a diamond in the middle of the screen. The diamond is printed by printing two halves, upper  
 * and lower. 
 *
 * 07. March, Lone Leth Thomsen
 **/

#include <ctype.h>
#include <stdio.h>

#define N 5                          


void repeat (char c, int how_many)    /* prints a character on the screen how_many times */
{
        int i;

        for (i=0; i < how_many; ++i)
                putchar(c);
}

int main(void)                        /* main program */
{
        char c = 'X';                     /* the character X will be printed */
        int i;

                                      /* upper half of diamond */
        for (i = 1; i < N; i += 1){       
                repeat(' ',(N-i));            /* prints blanks N-i times */
                repeat(c,i);                  /* then prints X i times */
                repeat(c,i);                  /* then prints X i times again */
                putchar('\n');                /* finally newline. Could also have been done by printing blanks again */
        };
                                          /* lower half of diamond */
        for (i = 1; i < N; i += 1){       
                repeat(' ',i);                /* prints blanks i times */      
                repeat(c,(N-i));              /* then prints X N-i times */           
                repeat(c,(N-i));              /* then prints X N-i times again */
                putchar('\n');                /* finally newline.  */     
        }
        return 0;
}