The nth term of the sequence of triangle numbers is given by, tn = ½n(n+1); so the first ten triangle numbers are:
1, 3, 6, 10, 15, 21, 28, 36, 45, 55, …
By converting each letter in a word to a number corresponding to its alphabetical position and adding these values we form a word value. For example, the word value for SKY is 19 + 11 + 25 = 55 = t10. If the word value is a triangle number then we shall call the word a triangle word.
Using words.txt (right click and ‘Save Link/Target As…’), a 16K text file containing nearly two-thousand common English words, how many are triangle words?
三角形词的数量
三角形数序列中第 n 项的定义是: tn = ½n(n+1); 因此前十个三角形数是:
1, 3, 6, 10, 15, 21, 28, 36, 45, 55, …
通过将一个单词中每个字母在字母表中的位置值加起来,我们可以将一个单词转换为一个数。例如,单词SKY的值为19 + 11 + 25 = 55 = t10。如果单词的值是一个三角形数,我们称这个单词为三角形单词。
words.txt (右键另存为)是一个16K的文本文件,包含将近两千个常用英语单词。在这个文件中,一共有多少个三角形词?
file = open('p042_words.txt')
n = [i * (i + 1) / 2 for i in range(1, 100)]
s = ''
for f in file:
s += f
s = eval(s)
def get_order(c):
return ord(c) - ord('A') + 1
count = 0
for word in s:
result = 0
for c in word:
result += get_order(c)
if result in n:
print word
count += 1
print count
家里网络太差了,各种github刷不出来……完全没法一天一题啊