20 lines
639 B
YAML
20 lines
639 B
YAML
title: Starting in the top left corner in a 20 by 20 grid, how many routes are there to the bottom right corner?
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url: http://projecteuler.net/problem=15
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desc: |
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Starting in the top left corner of a 22 grid, there are 6 routes (without backtracking) to the bottom right corner.
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How many routes are there through a 2020 grid?
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solution: |
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(2n)!/n!^2 - Where n is the size of the grid -
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todo: Find a more "programmable way" instead of this cheating mathsolution
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solutions:
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solve.php:
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desc: Using BCMath to cope with large numbers
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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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