1493. Longest Subarray of 1's After Deleting One Element

Author: remy727

README.md

@@ -165,6 +165,7 @@
 | 1472 | Design Browser History | [Ruby](./algorithms/ruby/1472-design-browser-history.rb) | Medium |
 | 1480 | Running Sum of 1d Array | [Ruby](./algorithms/ruby/1480-running-sum-of-1d-array.rb) | Easy |
 | 1491 | Average Salary Excluding the Minimum and Maximum Salary | [Ruby](./algorithms/ruby/1491-average-salary-excluding-the-minimum-and-maximum-salary.rb) | Easy |
+| 1493 | Longest Subarray of 1's After Deleting One Element | [Ruby](./algorithms/ruby/1493-longest-subarray-of-1s-after-deleting-one-element.rb) | Medium |
 | 1523 | Count Odd Numbers in an Interval Range | [Ruby](./algorithms/ruby/1523-count-odd-numbers-in-an-interval-range.rb) | Easy |
 | 1539 | Kth Missing Positive Number | [Ruby](./algorithms/ruby/1539-kth-missing-positive-number.rb) | Easy |
 | 1579 | Remove Max Number of Edges to Keep Graph Fully Traversable | [Ruby](./algorithms/ruby/1579-remove-max-number-of-edges-to-keep-graph-fully-traversable.rb) | Hard |

algorithms/ruby/1493-longest-subarray-of-1s-after-deleting-one-element.rb

@@ -0,0 +1,68 @@
+# frozen_string_literal: true
+
+# 1493. Longest Subarray of 1's After Deleting One Element
+# https://leetcode.com/problems/longest-subarray-of-1s-after-deleting-one-element
+# Medium
+
+=begin
+Given a binary array nums, you should delete one element from it.
+
+Return the size of the longest non-empty subarray containing only 1's in the resulting array. Return 0 if there is no such subarray.
+
+Example 1:
+Input: nums = [1,1,0,1]
+Output: 3
+Explanation: After deleting the number in position 2, [1,1,1] contains 3 numbers with value of 1's.
+
+Example 2:
+Input: nums = [0,1,1,1,0,1,1,0,1]
+Output: 5
+Explanation: After deleting the number in position 4, [0,1,1,1,1,1,0,1] longest subarray with value of 1's is [1,1,1,1,1].
+
+Example 3:
+Input: nums = [1,1,1]
+Output: 2
+Explanation: You must delete one element.
+
+Constraints:
+1 <= nums.length <= 105
+nums[i] is either 0 or 1.
+=end
+
+# @param {Integer[]} nums
+# @return {Integer}
+def longest_subarray(nums)
+  left = 0
+  right = 0
+  k = 1
+  max = 0
+
+  n = nums.size
+  while right < n
+    if nums[right] == 0
+      k -= 1
+      while k < 0
+        k += 1 if nums[left] == 0
+        left += 1
+      end
+    end
+    max = [max, right - left].max
+
+    right += 1
+  end
+
+  max
+end
+
+# **************** #
+#       TEST       #
+# **************** #
+
+require "test/unit"
+class Test_longest_subarray < Test::Unit::TestCase
+  def test_
+    assert_equal 3, longest_subarray([1, 1, 0, 1])
+    assert_equal 5, longest_subarray([0, 1, 1, 1, 0, 1, 1, 0, 1])
+    assert_equal 2, longest_subarray([1, 1, 1])
+  end
+end