多数人在入门编程语言的时候, 都接触过用代码实现九九乘法口诀表。以便大家尽快熟悉列表的遍历。
先手敲一遍
正三角形
# -*- coding: utf-8 -*-
def multiplication_tables():
for i in range(1, 10):
for j in range(1, i + 1):
print('%d * %d = %2d ' % (i, j, i * j), end='')
print('')
if __name__ == '__main__':
multiplication_tables()
输出结果:请注意排版的细微差异
1 * 1 = 1
2 * 1 = 2 2 * 2 = 4
3 * 1 = 3 3 * 2 = 6 3 * 3 = 9
4 * 1 = 4 4 * 2 = 8 4 * 3 = 12 4 * 4 = 16
5 * 1 = 5 5 * 2 = 10 5 * 3 = 15 5 * 4 = 20 5 * 5 = 25
6 * 1 = 6 6 * 2 = 12 6 * 3 = 18 6 * 4 = 24 6 * 5 = 30 6 * 6 = 36
7 * 1 = 7 7 * 2 = 14 7 * 3 = 21 7 * 4 = 28 7 * 5 = 35 7 * 6 = 42 7 * 7 = 49
8 * 1 = 8 8 * 2 = 16 8 * 3 = 24 8 * 4 = 32 8 * 5 = 40 8 * 6 = 48 8 * 7 = 56 8 * 8 = 64
9 * 1 = 9 9 * 2 = 18 9 * 3 = 27 9 * 4 = 36 9 * 5 = 45 9 * 6 = 54 9 * 7 = 63 9 * 8 = 72 9 * 9 = 81
扩展
应用场景:
有一个文本文件, 其中很多的句子句式相同,想通过相似度的算法, 只保留其中的一个句子。
将文本中, 每一句都进行相似度比较,若超过阈值, 则删除被对比的句子。低于阈值则保留。
最终得到的文件, 每一行之间的相似度都低于阈值。
Tips:
文本中, 其中一句与其余句子对比的算法,需要遍历文档,思路同乘法口诀表,只是形状是一个倒三角形。
倒三角形
# -*- coding: utf-8 -*-
def multiplication_tables_reverse():
for i in range(1, 10):
print(' ' * 13 * (i -1), end='') # 为了倒三角形比较明显
for j in range(i, 10):
print('%d * %d = %2d ' % (i, j, i * j), end='')
print('')
if __name__ == '__main__':
multiplication_tables_reverse()
输出结果:请注意排版的细微差异
1 * 1 = 1 1 * 2 = 2 1 * 3 = 3 1 * 4 = 4 1 * 5 = 5 1 * 6 = 6 1 * 7 = 7 1 * 8 = 8 1 * 9 = 9
2 * 2 = 4 2 * 3 = 6 2 * 4 = 8 2 * 5 = 10 2 * 6 = 12 2 * 7 = 14 2 * 8 = 16 2 * 9 = 18
3 * 3 = 9 3 * 4 = 12 3 * 5 = 15 3 * 6 = 18 3 * 7 = 21 3 * 8 = 24 3 * 9 = 27
4 * 4 = 16 4 * 5 = 20 4 * 6 = 24 4 * 7 = 28 4 * 8 = 32 4 * 9 = 36
5 * 5 = 25 5 * 6 = 30 5 * 7 = 35 5 * 8 = 40 5 * 9 = 45
6 * 6 = 36 6 * 7 = 42 6 * 8 = 48 6 * 9 = 54
7 * 7 = 49 7 * 8 = 56 7 * 9 = 63
8 * 8 = 64 8 * 9 = 72
9 * 9 = 81