Buggy python submission (verdict: Runtime Error):
while True:
    H, W = [int(i) for i in input().split()]

        if H + W % == 0:
            print('#')

        else:
            print('.')

    print

        

Fixed submission:
while True:
    H, W = [int(i) for i in input().split()]
    if H == W == 0:
       break

    for h in range(H):
        for w in range(W):
            if (h + w) % 2 == 0:
                print('#', end='')
            else:
                print('.', end='')

        print()
    print()

Buggy python submission (verdict: Runtime Error):
while True:
    H, W = [int(i) for i in input().split()]

    if H + W % == 0
        print('#')

    else:
        print('.')

print

        

Fixed submission:
while True:
    H, W = [int(i) for i in input().split()]
    if H == W == 0:
       break

    for h in range(H):
        for w in range(W):
            if (h + w) % 2 == 0:
                print('#', end='')
            else:
                print('.', end='')

        print()
    print()

Buggy python submission (verdict: Runtime Error):
while True:
    H, W = [int(i) for i in input().split()]

        if H + W % == 0
            print('#')
        else:
            print('.')

    print

        

Fixed submission:
while True:
    H, W = [int(i) for i in input().split()]
    if H == W == 0:
       break

    for h in range(H):
        for w in range(W):
            if (h + w) % 2 == 0:
                print('#', end='')
            else:
                print('.', end='')

        print()
    print()

Buggy python submission (verdict: Runtime Error):
while True:
    H, W = [int(i) for i in input().split()]

        if H + W % == 0:
            print('#')
        else:
            print('.')

    print

        

Fixed submission:
while True:
    H, W = [int(i) for i in input().split()]
    if H == W == 0:
       break

    for h in range(H):
        for w in range(W):
            if (h + w) % 2 == 0:
                print('#', end='')
            else:
                print('.', end='')

        print()
    print()

Buggy python submission (verdict: Runtime Error):
while True:
    h, w = [int(i) for i in input().split()]

        if (h + w) % 2 = 0:
            print('#')
        else:
            print('.')

    print

        

Fixed submission:
while True:
    H, W = [int(i) for i in input().split()]
    if H == W == 0:
       break

    for h in range(H):
        for w in range(W):
            if (h + w) % 2 == 0:
                print('#', end='')
            else:
                print('.', end='')

        print()
    print()

Buggy python submission (verdict: Runtime Error):
while True:
    H, W = [int(i) for i in input().split()]
    if H == W == 0:
       break
    
    if (h + w) % 2 = 0:
            print('#', end='')
    else:
            print('.', end='')

    print()

        

Fixed submission:
while True:
    H, W = [int(i) for i in input().split()]
    if H == W == 0:
       break

    for h in range(H):
        for w in range(W):
            if (h + w) % 2 == 0:
                print('#', end='')
            else:
                print('.', end='')

        print()
    print()

Buggy python submission (verdict: Runtime Error):
while True:
    H, W = [int(i) for i in input().split()]
    if H == W == 0:
       break
    for h in range(H):
        for w in range(W):
            if (h + w) % 2 = 0:
                print('#', end='')
        else:
                print('.', end='')

        print()

        

Fixed submission:
while True:
    H, W = [int(i) for i in input().split()]
    if H == W == 0:
       break

    for h in range(H):
        for w in range(W):
            if (h + w) % 2 == 0:
                print('#', end='')
            else:
                print('.', end='')

        print()
    print()

Buggy python submission (verdict: Runtime Error):
while True:
    H, W = [int(i) for i in input().split()]
    if H == W == 0:
       break

    for h in range(H):
        for w in range(W):
            if (h + w) % 2 = 0:
                print('#', end='')
        else:
                print('.', end='')

        print()

        

Fixed submission:
while True:
    H, W = [int(i) for i in input().split()]
    if H == W == 0:
       break

    for h in range(H):
        for w in range(W):
            if (h + w) % 2 == 0:
                print('#', end='')
            else:
                print('.', end='')

        print()
    print()