Created
October 17, 2012 03:20
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Attempt to re-write the code
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#Problem 12: | |
# The sequence of triangle numbers is generated by adding the natural numbers. So the 7th triangle number would be 1 + 2 + 3 + 4 + 5 + 6 + 7 = 28. The first ten terms would be: | |
# 1, 3, 6, 10, 15, 21, 28, 36, 45, 55, ... | |
# Let us list the factors of the first seven triangle numbers: | |
# 1: 1 | |
# 3: 1,3 | |
# 6: 1,2,3,6 | |
# 10: 1,2,5,10 | |
# 15: 1,3,5,15 | |
# 21: 1,3,7,21 | |
# 28: 1,2,4,7,14,28 | |
# We can see that 28 is the first triangle number to have over five divisors. | |
# What is the value of the first triangle number to have over five hundred divisors? | |
def compute(n) | |
$triagnum = [] | |
# $factor = [] | |
for x in (1..n) | |
$triagnum << (1..x).inject(0, :+) | |
end | |
$triagnum.each do |x| | |
n = 0 | |
(1..x).each do |y| | |
if x % y == 0 | |
n += 1 | |
end | |
end | |
p "Triangle Number #{x} has #{n} divisors" | |
break if n >= 500 | |
end | |
end | |
# First attempt to try and find the answer | |
# | |
# for x in $triagnum | |
# factor = [] | |
# (1..x).each do |y| | |
# if x % y == 0 | |
# factor << y | |
# end | |
# end | |
# $factor << [x, factor] | |
# end | |
# p "The triangle number #{$factor.last[0]} has #{$factor.last[1].count} divisors" | |
# | |
# n = 500 | |
# for x in (400..n) | |
# compute x | |
# break if $factor.last[1].count >= 500 | |
# n += 1 | |
# end |
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