#define   AlphaCount   26
  int i,j;

  char Alpha[AlphaCount];
  for(i=0 ;i<AlphaCount ;i++) Alpha[i]='A'+i;

  for(i=0 ;i<AlphaCount+1 ;i++){
   for(j=i ;j<i+AlphaCount ;j++){
     printf("%c",Alpha[j%AlphaCount]);
   }
   printf("\n");
  }

 

배열이 필요 없다면 아래와 같이.

  #define   AlphaCount   26
  int i,j;

  for(i=0 ;i<AlphaCount+1 ;i++){
   for(j=i ;j<i+AlphaCount ;j++){
     printf("%c",'A'+j%AlphaCount);
   }
   printf("\n");
  }


양수의 경우 % 연산의 결과는 0~젯수-1입니다.
위에서는 젯수가 26이므로 %연산의 결과는 0~25가 됩니다.
0%26=0
1%26=1
2%26=2
.
.
.
25%26=25
26%26=0
27%26=1
28%26=2
.
.
.
51%26=25
52%26=0



김성은 님이 쓰신 글 :
: 실행결과가 아래와 같이 나와야 하는데요......
: 배열로 해야하는건데 넘 어려워요 ㅠ_ㅠ 알려주세요 ㅠ_ㅠ
: 아참 터보 C 입니다..;;
:
: ------------------실행 결과-------------------------------
:
: ABCDEFGHIJKLMNOPQRSTUVWXYZ
: BCDEFGHIJKLMNOPQRSTUVWXYZA
: CDEFGHIJKLMNOPQRSTUVWXYZAB
: DEFGHIJKLMNOPQRSTUVWXYZABC
: EFGHIJKLMNOPQRSTUVWXYZABCD
: FGHIJKLMNOPQRSTUVWXYZABCDE
: GHIJKLMNOPQRSTUVWXYZABCDEF
: HIJKLMNOPQRSTUVWXYZABCDEFG
: IJKLMNOPQRSTUVWXYZABCDEFGH
: JKLMNOPQRSTUVWXYZABCDEFGHI
: KLMNOPQRSTUVWXYZABCDEFGHIJ
: LMNOPQRSTUVWXYZABCDEFGHIJK
: MNOPQRSTUVWXYZABCDEFGHIJKL
: NOPQRSTUVWXYZABCDEFGHIJKLM
: OPQRSTUVWXYZABCDEFGHIJKLMN
: PQRSTUVWXYZABCDEFGHIJKLMNO
: QRSTUVWXYZABCDEFGHIJKLMNOP
: RSTUVWXYZABCDEFGHIJKLMNOPQ
: STUVWXYZABCDEFGHIJKLMNOPQR
: TUVWXYZABCDEFGHIJKLMNOPQRS
: UVWXYZABCDEFGHIJKLMNOPQRST
: VWXYZABCDEFGHIJKLMNOPQRSTU
: WXYZABCDEFGHIJKLMNOPQRSTUV
: XYZABCDEFGHIJKLMNOPQRSTUVW
: YZABCDEFGHIJKLMNOPQRSTUVWX
: ZABCDEFGHIJKLMNOPQRSTUVWXY
: ABCDEFGHIJKLMNOPQRSTUVWXYZ
:
: -----------------------------------------
: