0219-contains-duplicate-ii.rb

# frozen_string_literal: true

# 219. Contains Duplicate II
# https://leetcode.com/problems/contains-duplicate-ii
# Easy

=begin
Given an integer array nums and an integer k, return true if there are two distinct indices i and j in the array such that nums[i] == nums[j] and abs(i - j) <= k.

Example 1:
Input: nums = [1,2,3,1], k = 3
Output: true

Example 2:
Input: nums = [1,0,1,1], k = 1
Output: true

Example 3:
Input: nums = [1,2,3,1,2,3], k = 2
Output: false

Constraints:
1 <= nums.length <= 105
-109 <= nums[i] <= 109
0 <= k <= 105
=end

# @param {Integer[]} nums
# @param {Integer} k
# @return {Boolean}
defcontains_nearby_duplicate(nums,k)
hash={}
nums.each_with_indexdo |value,j|
i=hash[value]
ifi && (j - i) <= k
returntrue
end
hash[value]=j
end
false
end

# **************** #
# TEST #
# **************** #

require"test/unit"
classTest_contains_nearby_duplicate < Test::Unit::TestCase
deftest_
assert_equaltrue,contains_nearby_duplicate([1,2,3,1],3)
assert_equaltrue,contains_nearby_duplicate([1,0,1,1],1)
assert_equalfalse,contains_nearby_duplicate([1,2,3,1,2,3],2)
end
end