하루종일 이슈 잡다보니 몸은 피곤한데.. 신경이 살아서 잠이 안오네.. ㅡㅡ;
맘에 안드네.. 여튼.. 음.. 좀더 깔끔하게 바꿔봐... 더 좋은 방법이 있을것 같은데..
머리가 멍해서리.. ㅋㅋ

void print(int width, int num)
{
  int space = (width-num)/2;
  int mid = (num/2)-1;
  int i,n=0;
  
  if(space)
    printf("%*c", space, ' ');

  for(i=0; i < num; i++)
  {
    printf("%c", 'A'+n);
    if(i <= mid) n++;
    else n--;
  }
  printf("\n");
}


void main()
{
  int n, mid, step;

  while(1)
  {
    printf("\ninput line (0=exit) : ");
    scanf("%d",&n);

    if(n<=0) break;
    if(!(n%2)) n--;

    mid = (n/2)-1;
    step = 1;
    for(int i=0; i < n; i++)
    {
      print(n, step);
      if(i <= mid) step+=2;
      else step-=2;
    }
  }
}

ㅋㅋㅋ

input line (0=exit) : 51
                         A
                        ABA
                       ABCBA
                      ABCDCBA
                     ABCDEDCBA
                    ABCDEFEDCBA
                   ABCDEFGFEDCBA
                  ABCDEFGHGFEDCBA
                 ABCDEFGHIHGFEDCBA
                ABCDEFGHIJIHGFEDCBA
               ABCDEFGHIJKJIHGFEDCBA
              ABCDEFGHIJKLKJIHGFEDCBA
             ABCDEFGHIJKLMLKJIHGFEDCBA
            ABCDEFGHIJKLMNMLKJIHGFEDCBA
           ABCDEFGHIJKLMNONMLKJIHGFEDCBA
          ABCDEFGHIJKLMNOPONMLKJIHGFEDCBA
         ABCDEFGHIJKLMNOPQPONMLKJIHGFEDCBA
        ABCDEFGHIJKLMNOPQRQPONMLKJIHGFEDCBA
       ABCDEFGHIJKLMNOPQRSRQPONMLKJIHGFEDCBA
      ABCDEFGHIJKLMNOPQRSTSRQPONMLKJIHGFEDCBA
     ABCDEFGHIJKLMNOPQRSTUTSRQPONMLKJIHGFEDCBA
    ABCDEFGHIJKLMNOPQRSTUVUTSRQPONMLKJIHGFEDCBA
   ABCDEFGHIJKLMNOPQRSTUVWVUTSRQPONMLKJIHGFEDCBA
  ABCDEFGHIJKLMNOPQRSTUVWXWVUTSRQPONMLKJIHGFEDCBA
ABCDEFGHIJKLMNOPQRSTUVWXYXWVUTSRQPONMLKJIHGFEDCBA
ABCDEFGHIJKLMNOPQRSTUVWXYZYXWVUTSRQPONMLKJIHGFEDCBA
ABCDEFGHIJKLMNOPQRSTUVWXYXWVUTSRQPONMLKJIHGFEDCBA
  ABCDEFGHIJKLMNOPQRSTUVWXWVUTSRQPONMLKJIHGFEDCBA
   ABCDEFGHIJKLMNOPQRSTUVWVUTSRQPONMLKJIHGFEDCBA
    ABCDEFGHIJKLMNOPQRSTUVUTSRQPONMLKJIHGFEDCBA
     ABCDEFGHIJKLMNOPQRSTUTSRQPONMLKJIHGFEDCBA
      ABCDEFGHIJKLMNOPQRSTSRQPONMLKJIHGFEDCBA
       ABCDEFGHIJKLMNOPQRSRQPONMLKJIHGFEDCBA
        ABCDEFGHIJKLMNOPQRQPONMLKJIHGFEDCBA
         ABCDEFGHIJKLMNOPQPONMLKJIHGFEDCBA
          ABCDEFGHIJKLMNOPONMLKJIHGFEDCBA
           ABCDEFGHIJKLMNONMLKJIHGFEDCBA
            ABCDEFGHIJKLMNMLKJIHGFEDCBA
             ABCDEFGHIJKLMLKJIHGFEDCBA
              ABCDEFGHIJKLKJIHGFEDCBA
               ABCDEFGHIJKJIHGFEDCBA
                ABCDEFGHIJIHGFEDCBA
                 ABCDEFGHIHGFEDCBA
                  ABCDEFGHGFEDCBA
                   ABCDEFGFEDCBA
                    ABCDEFEDCBA
                     ABCDEDCBA
                      ABCDCBA
                       ABCBA
                        ABA
                         A

input line (0=exit) :