Diamond Shape Using Alphabet

Write a program to create the following Pyramid using C program?

                   A
          A B
        A B C
       A B C D
     A B C D E
   A B C D E F
           A B C D E
A B C D
A B C
A B
A  

*****************************Program************************

#include<stdio.h>
#include<conio.h>
main()
{
 int r,c,k,m,i;
 printf("Enter the number of lines : ");
 scanf("%d",&m);
 for(r=1;r<=m-1;r++)
    {
        i=0;
        for(c=1;c<=m-r;c++)
        {
            printf(" ");
        }
        for(k=1;k<=r;k++)
        {
            printf("%c ",65+i);
            i++;
        }
        printf("\n");
    }
    for(r=0;r<=m-1;r++)
    {
        i=0;
        for(k=1;k<=r;k++)
        {
            printf(" ");
        }
        for(c=1;c<=m-r;c++)
        {
            printf("%c ",65+i);
            i++;
        }
        printf("\n");
    }
    getch();
 return 0;
}

*****************************Output*************************

screen shot for Diamond shape using alphabet