31 lines
803 B
Ruby
31 lines
803 B
Ruby
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# frozen_string_literal: true
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# Given an integer array nums, return true if any value appears at least,
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# twice in the array and return false if every element is distinct.
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# Example:
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# Input: nums = [1, 2, 3, 1]
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# Output: true
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# Time: O(n)
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# Space: O(n)
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module Arrays
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def self.contains_duplicate(nums)
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!nums.uniq!.nil?
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end
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end
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RSpec.describe Arrays do
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describe '.contains_duplicate(nums)' do
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it 'returns true if any value appears at least twice in the array' do
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expect(Arrays.contains_duplicate([1, 2, 3, 1])).to be true
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end
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it 'returns false if every element is distinct' do
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expect(Arrays.contains_duplicate([1, 2, 3, 4])).to be false
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end
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it 'returns false for an empty array' do
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expect(Arrays.contains_duplicate([])).to be false
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end
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end
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end
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