Problem 42 - How many triangle words does the list of common English words contain?

링크

The n^th term of the sequence of triangle numbers is given by, t_n = 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?

python

file = open("./words.txt") words = file.read() words = words.replace('"', '') words = words.split(',') file.close() tn = [n*(n+1)/2 for n in range(1, 50)] cnt = 0 for word in words: s = sum(ord(ch)-ord('A')+1 for ch in word) if s in tn: cnt += 1 print cnt