triangle_from_desired_numbers_v1.c

/*

    triangle_from_desired_numbers_v1.c

    Task:
    https://web.facebook.com/photo.php?fbid=863006627544618&set=gm.1579899445502233&type=3&theater

---------1
--------212
-------82128
------6821286
-----068212860
----20682128602
---8206821286028
--682068212860286
-06820682128602860
2068206821286028602

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

    https://pastebin.com/u/dmilicev

*/

#include <stdio.h>

// Draw n rows of a triangle with numbers
void draw_trinagle_of_numbers( int n )
{
    int num[4]={2,8,6,0};               // array of desired digits
    int i,row, index=0, ns, nd;         // ns number of spaces, nd number of digits
                                        // index is for array num[index] that we print
    for (row=0; row<n; row++)           // print rows one by one row
    {
        ns = n-row-1;                   // calculate ns number of spaces
        nd = (2*row+1)/2;               // calculate nd number of digits

        for (i=0; i<ns; i++)            // print ns spaces " "
            printf("-");

        for(i=0; i<nd; i++)             // print nd "%d " numbers
        {
            printf("%d", num[index] );
            if(index>0)
                index--;
            else
                index=3;
        }

        printf("%d", 1 );               // printf digit 1 in middle

        index = 0;
        for(i=0; i<nd; i++)             // print nd "%d " numbers
        {
            printf("%d", num[index] );
            if(index<3)
                index++;
            else
                index=0;
        }

        printf("\n");
    }
}


int main(void)
{
    draw_trinagle_of_numbers( 10 );

    return 0;

} // main()