1 输出九九乘法表

请写一个python代码输出九九乘法表

输出：

1 x 1 = 1       1 x 2 = 2       1 x 3 = 3       1 x 4 = 4       1 x 5 = 5        1 x 6 = 6       1 x 7 = 7       1 x 8 = 8       1 x 9 = 9
2 x 2 = 4       2 x 3 = 6       2 x 4 = 8       2 x 5 = 10      2 x 6 = 12       2 x 7 = 14      2 x 8 = 16      2 x 9 = 18
3 x 3 = 9       3 x 4 = 12      3 x 5 = 15      3 x 6 = 18      3 x 7 = 21       3 x 8 = 24      3 x 9 = 27
4 x 4 = 16      4 x 5 = 20      4 x 6 = 24      4 x 7 = 28      4 x 8 = 32       4 x 9 = 36
5 x 5 = 25      5 x 6 = 30      5 x 7 = 35      5 x 8 = 40      5 x 9 = 45
6 x 6 = 36      6 x 7 = 42      6 x 8 = 48      6 x 9 = 54
7 x 7 = 49      7 x 8 = 56      7 x 9 = 63
8 x 8 = 64      8 x 9 = 72
9 x 9 = 81

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1.1 输出 1 x 1 = 1

知识点：输出语法 print()

答案

print("1 x 1 = 1")

1.2 输出一个 a x b = c

知识点：输出占位符，例如

print("My name is %s and I'm %d years old." % (name, age))

答案

print("%d x %d = %d" % (1, 1, 1*1)) # 1 * 1 = 1

print("%d x %d = %d" % (2, 3, 2*3)) # 2 * 3 = 6

1.3 输出 1 x b = b

知识点：循环

for 变量 in 序列:
    循环体

知识点：1 ~ 9 的序列

答案

1 ~ 9 的序列 range(1, 10)

for b in range(1, 10):
    print("%d x %d = %d" % (1, b, 1 * b))

输出：

1 x 1 = 1
1 x 2 = 2
1 x 3 = 3
1 x 4 = 4
1 x 5 = 5
1 x 6 = 6
1 x 7 = 7
1 x 8 = 8
1 x 9 = 9

知识点：输出结尾格式 end="\t"

让这些显示成一行

答案

for b in range(1, 10):
    print("%d x %d = %d" % (1, b, 1 * b), end="\t")

1.4 输出九九乘法表

知识点：循环嵌套

a x b = c

a = 1 时，b = 1 ~ 9
a = 2 时，b = 2 ~ 9
a = 3 时，b = 3 ~ 9

答案

for a in range(1, 10):
    for b in range(a, 10):
        print("%d x %d = %d" % (a, b, a * b), end="\t")
    print()   # 空一行

输出：

1 x 1 = 1       1 x 2 = 2       1 x 3 = 3       1 x 4 = 4       1 x 5 = 5        1 x 6 = 6       1 x 7 = 7       1 x 8 = 8       1 x 9 = 9
2 x 2 = 4       2 x 3 = 6       2 x 4 = 8       2 x 5 = 10      2 x 6 = 12       2 x 7 = 14      2 x 8 = 16      2 x 9 = 18
3 x 3 = 9       3 x 4 = 12      3 x 5 = 15      3 x 6 = 18      3 x 7 = 21       3 x 8 = 24      3 x 9 = 27
4 x 4 = 16      4 x 5 = 20      4 x 6 = 24      4 x 7 = 28      4 x 8 = 32       4 x 9 = 36
5 x 5 = 25      5 x 6 = 30      5 x 7 = 35      5 x 8 = 40      5 x 9 = 45
6 x 6 = 36      6 x 7 = 42      6 x 8 = 48      6 x 9 = 54
7 x 7 = 49      7 x 8 = 56      7 x 9 = 63
8 x 8 = 64      8 x 9 = 72
9 x 9 = 81

1.5 知识点

考察知识点：循环，范围

Python 代码练习--基础语法--输出九九乘法表