def print_rangoli(n):
    matrix = [["-"]*(n*4-3) for _ in range(n)]
    for i, row in enumerate(matrix):
        matrix[i] = editRow(row, i, n*4-3, n)
        
    for row in matrix:
        print(row)
        
    for row in matrix[:n-1][::-1]:
        print(row)
        

def editRow(row, indx, length, n):
    i = length//2
    row[i] = chr(97+n-indx-1)
    prev = ord(row[i])
    for _ in range(indx):
        i -= 2
        row[i] = row[-i-1] = chr(prev+1)
        prev = ord(row[i])
        
    return "".join(row)
    

if __name__ == '__main__':
    n = int(input())
    print_rangoli(n)