Merge pull request #712 from fartem/134_Gas_Station

2024-08-19 v. 6.5.0: added "134. Gas Station"

Author: fartem

README.md

@@ -515,3 +515,4 @@ Profile on LeetCode: [fartem](https://leetcode.com/fartem/).
 | 128. Longest Consecutive Sequence                               | [Link](https://leetcode.com/problems/longest-consecutive-sequence/)                               | [Link](./lib/medium/128_longest_consecutive_sequence.rb)                               |
 | 129. Sum Root to Leaf Numbers                                   | [Link](https://leetcode.com/problems/sum-root-to-leaf-numbers/)                                   | [Link](./lib/medium/129_sum_root_to_leaf_numbers.rb)                                   |
 | 133. Clone Graph                                                | [Link](https://leetcode.com/problems/clone-graph/)                                                | [Link](./lib/medium/133_clone_graph.rb)                                                |
+| 134. Gas Station                                                | [Link](https://leetcode.com/problems/gas-station/)                                                | [Link](./lib/medium/134_gas_station.rb)                                                |

leetcode-ruby.gemspec

@@ -5,7 +5,7 @@ require 'English'
 ::Gem::Specification.new do |s|
   s.required_ruby_version = '>= 3.0'
   s.name = 'leetcode-ruby'
-  s.version = '6.4.9'
+  s.version = '6.5.0'
   s.license = 'MIT'
   s.files = ::Dir['lib/**/*.rb'] + %w[README.md]
   s.executable = 'leetcode-ruby'

lib/medium/134_gas_station.rb

@@ -0,0 +1,24 @@
+# frozen_string_literal: true
+
+# https://leetcode.com/problems/gas-station/
+# @param {Integer[]} gas
+# @param {Integer[]} cost
+# @return {Integer}
+def can_complete_circuit(gas, cost)
+  tmp_sum = 0
+  index = 0
+  sum = gas.first - cost.first
+  (1...gas.size).each do |i|
+    if sum.negative?
+      index = i
+      tmp_sum += sum
+      sum = 0
+    end
+
+    sum += gas[i] - cost[i]
+  end
+
+  sum += tmp_sum
+
+  sum >= 0 ? index : -1
+end

test/medium/test_134_gas_station.rb

@@ -0,0 +1,24 @@
+# frozen_string_literal: true
+
+require_relative '../test_helper'
+require_relative '../../lib/medium/134_gas_station'
+require 'minitest/autorun'
+
+class GasStationTest < ::Minitest::Test
+  def test_default
+    assert_equal(
+      3,
+      can_complete_circuit(
+        [1, 2, 3, 4, 5],
+        [3, 4, 5, 1, 2]
+      )
+    )
+    assert_equal(
+      -1,
+      can_complete_circuit(
+        [2, 3, 4],
+        [3, 4, 3]
+      )
+    )
+  end
+end