1307 : 문자사각형1

n = int(input())

arr=[[0 for i in range(n+1)] for j in range(n+1)]
alph = ord('A')

for i in range(n):
    for j in range(n):
        arr[n-j][n-i]=alph
        alph+=1
        if alph > ord('Z'):
            alph=ord('A')

for i in range(1,n+1):
    for j in range(1,n+1):
        print(chr(arr[i][j]),end=' ')
    print()