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@dharshan
Last active Nov 19, 2017
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Find any pairs of numbers in a sequence that add up to sum N (Using builtin combination method)
##### OUTPUT
1
Enter comma seperated integers
1,2,3,4,6,7,8
Enter pair sum
10
[[2, 8], [3, 7], [4, 6]]
2
Enter comma seperated integers
1,2,3,4,6,7,8
Enter pair sum
5
[[1, 4], [2, 3]]
3
Enter comma seperated integers
1,2,3,4,6,7,8
Enter pair sum
20
[]
4
Enter comma seperated integers
1,2,3,4,6,7,a
Invalid Input (Only Integers allowed)
# Find any pairs of numbers in a sequence that add up to sum N.
# Given input 1, 8, 2, 3, 5, 7
# Expected Output (8,2), (3, 7)
# Using built-in function combination to check and compare sum pair value
class CheckPairs
# Base class to instantiate utility class
def find_pairs
nums,sum = user_input
num_pairs = NumPairs.new(nums, sum)
pairs = num_pairs.pairs
p pairs
end
def user_input # Takes user input and returns to calling function as arrays
p 'Enter comma seperated integers'
nums = gets.chomp
if nums.split(',').join('').scan(/\D/).empty?
p 'Enter pair sum'
sum = gets.chomp.to_i
return [nums, sum]
else
p 'Invalid Input (Only Integers allowed)'
exit
end
end
end
class NumPairs
# Utility class to perform required functions
def initialize(numbers, sum) # Initialize numbers and sum
@numbers = numbers.split(',').map(&:to_i).uniq
@sum = sum.to_i
end
def pairs
@numbers.combination(2).select { |x, y| x + y == @sum}
end
end
pairs = CheckPairs.new
pairs.find_pairs
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