python：四種形狀的九九乘法表

# 九九乘法表一
for i in range(1, 10):
    for j in range(1, i + 1):
        print('{} * {} = {: <2}'.format(j, i, i*j), end=' ')
    print()

# 九九乘法表二
for i in range(1, 10):
    i = 10 - i
    for j in range(1, i + 1):
        print('{} * {} = {: <2}'.format(j, i, i * j), end=' ')
    print()

# 九九乘法表三
for i in range(1, 10):
    for j in range(1, 10 - i):
        print(' '*11, end='')
    v = i
    for k in range(1, i + 1):
        print('{} * {} = {: <2}'.format(v, i, i * v), end=' ')
        v -= 1
    print()

# 九九乘法表四
for i in range(1, 10):
    for j in range(1, i):
        print(' '*11, end='')
    v = 10 - i
    for k in range(1, 11 - i):
        c = 10 - i
        print('{} * {} = {: <2}'.format(v, c, c * v), end=' ')
        v -= 1
    print()