#---------------------------- Alternative 1's and 0's ---------------------------------

num= int(input("Enter a number : "))
for i in range(num):
    for j in range(num):
        if(i % 2 ==0 ):
            print('1',end='')
    
        else:
            print('0',end='')
    print()

#---------------------------- Alternative 0's and 1's -------------------------------------

num= int(input("Enter a number : "))
for i in range(num):
    for j in range(num):
        print(i % 2 ,end='')
    print()

#---------------------------- Hallow square/ frame symbol------------------------------------
   
num = int(input("Enter number: "))
for i in range(num+1):
    for j in range(num+1):
        if (i == 0 or i == num or j == 0 or j == num):
            print("* ", end='')
        else:
            print("  ", end='')
    print()

#---------------------------- Hallow square/ frame number------------------------------------

num = int(input("Enter number: "))
for i in range(num+1):
    for j in range(num+1):
        if (i == 0 or i == num or j == 0 or j == num):
            print(i, end=' ' )
        else:
            print("  ", end='')
    print()

#---------------------------- Hallow square/ frame albhabets----------------------------------

num = int(input("Enter number: "))
asc = 65
for i in range(num+1):
    for j in range(num+1):
        if (i == 0 or i == num or j == 0 or j == num):
            print(chr(asc+i), end=' ' )
        else:
            print("  ", end='')
    print()

#---------------------------- Alternative 0's and 1's in one line ----------------------------

num= int(input("Enter a number : "))
for i in range(num):
    for j in range(num):
        if((i+j)%2 == 0 and i % 2 == j % 2 ):
            print("1",end='')
        else:
            print("0",end='')
       
    print()