33 lines
938 B
YAML
33 lines
938 B
YAML
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title: What is the sum of both diagonals in a 1001 by 1001 spiral?
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url: http://projecteuler.net/problem=28
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desc: |
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Starting with the number 1 and moving to the right in a clockwise direction a 5 by 5 spiral is formed as follows:
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21 22 23 24 25
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20 7 8 9 10
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19 6 1 2 11
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18 5 4 3 12
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17 16 15 14 13
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It can be verified that the sum of the numbers on the diagonals is 101.
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What is the sum of the numbers on the diagonals in a 1001 by 1001 spiral formed in the same way?
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solution: |
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Step around in the spiral (add 2 - 3 times, then add 4 - 3times, then 6 - times etc)
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solutions:
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solve.php:
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desc: Basic solution
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language: php
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solve.rb:
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desc: Basic solution
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language: ruby
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solve.c:
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desc: ANSI C solution (Tested with TCC)
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language: c
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solve.js:
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desc: NodeJS solution
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language: javascript
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solve.lua:
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desc: Basic solution
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language: lua
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