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Commit 67bb9f9

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Merge pull request #397 from 0xff-dev/134
Add solution and test-cases for problem 134
2 parents 19a838e + 87abab3 commit 67bb9f9

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# [134. Gas Station][title]
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## Description
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There are `n` gas stations along a circular route, where the amount of gas at the i<sup>th</sup> station is `gas[i]`.
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You have a car with an unlimited gas tank and it costs `cost[i]` of gas to travel from the i<sup>th</sup> station to its next (i + 1)<sup>th</sup> station. You begin the journey with an empty tank at one of the gas stations.
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Given two integer arrays `gas` and `cost`, return the starting gas station's index if you can travel around the circuit once in the clockwise direction, otherwise return `-1`. If there exists a solution, it is **guaranteed** to be **unique**
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**Example 1:**
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```
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Input: gas = [1,2,3,4,5], cost = [3,4,5,1,2]
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Output: 3
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Explanation:
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Start at station 3 (index 3) and fill up with 4 unit of gas. Your tank = 0 + 4 = 4
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Travel to station 4. Your tank = 4 - 1 + 5 = 8
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Travel to station 0. Your tank = 8 - 2 + 1 = 7
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Travel to station 1. Your tank = 7 - 3 + 2 = 6
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Travel to station 2. Your tank = 6 - 4 + 3 = 5
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Travel to station 3. The cost is 5. Your gas is just enough to travel back to station 3.
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Therefore, return 3 as the starting index.
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```
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**Example 2:**
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```
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Input: gas = [2,3,4], cost = [3,4,3]
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Output: -1
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Explanation:
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You can't start at station 0 or 1, as there is not enough gas to travel to the next station.
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Let's start at station 2 and fill up with 4 unit of gas. Your tank = 0 + 4 = 4
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Travel to station 0. Your tank = 4 - 3 + 2 = 3
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Travel to station 1. Your tank = 3 - 3 + 3 = 3
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You cannot travel back to station 2, as it requires 4 unit of gas but you only have 3.
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Therefore, you can't travel around the circuit once no matter where you start.
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```
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## 结语
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如果你同我一样热爱数据结构、算法、LeetCode,可以关注我 GitHub 上的 LeetCode 题解:[awesome-golang-algorithm][me]
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[title]: https://leetcode.com/problems/gas-station/
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[me]: https://github.com/kylesliu/awesome-golang-algorithm
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package Solution
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func Solution(x bool) bool {
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return x
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func Solution(gas []int, cost []int) int {
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l := len(gas)
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tank, total, target := 0, 0, 0
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for i := 0; i < l; i++ {
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tank += gas[i] - cost[i]
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if tank < 0 {
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target = i + 1
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total += tank
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tank = 0
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}
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}
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if tank+total < 0 {
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return -1
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}
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return target
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}

‎leetcode/101-200/0134.Gas-Station/Solution_test.go‎

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func TestSolution(t *testing.T) {
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// 测试用例
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cases := []struct {
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name string
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inputsbool
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expect bool
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name string
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gas, cost []int
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expect int
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}{
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{"TestCase", true, true},
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{"TestCase", true, true},
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{"TestCase", false, false},
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{"TestCase1", []int{1, 2, 3, 4, 5}, []int{3, 4, 5, 1, 2}, 3},
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{"TestCase2", []int{2, 3, 4}, []int{3, 4, 3}, -1},
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}
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// 开始测试
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for i, c := range cases {
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t.Run(c.name+" "+strconv.Itoa(i), func(t *testing.T) {
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got := Solution(c.inputs)
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got := Solution(c.gas, c.cost)
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if !reflect.DeepEqual(got, c.expect) {
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t.Fatalf("expected: %v, but got: %v, with inputs: %v",
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c.expect, got, c.inputs)
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t.Fatalf("expected: %v, but got: %v, with inputs: %v %v",
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c.expect, got, c.gas, c.cost)
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}
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})
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}
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}
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//压力测试
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//压力测试
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func BenchmarkSolution(b *testing.B) {
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}
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//使用案列
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//使用案列
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func ExampleSolution() {
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}

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