Merge pull request 6boris#1289 from 0xff-dev/2110

Add solution and test-cases for problem 2110

Author: 6boris

leetcode/2101-2200/2110.Number-of-Smooth-Descent-Periods-of-a-Stock/README.md

@@ -1,28 +1,38 @@
 # [2110.Number of Smooth Descent Periods of a Stock][title]
 
-> [!WARNING|style:flat]
-> This question is temporarily unanswered if you have good ideas. Welcome to [Create Pull Request PR](https://github.com/kylesliu/awesome-golang-algorithm)
-
 ## Description
+You are given an integer array `prices` representing the daily price history of a stock, where `prices[i]` is the stock price on the `ith` day.
+
+A **smooth descent period** of a stock consists of **one or more contiguous** days such that the price on each day is **lower** than the price on the **preceding day** by **exactly** `1`. The first day of the period is exempted from this rule.
+
+Return the number of **smooth descent periods**.
 
 **Example 1:**
 
 ```
-Input: a = "11", b = "1"
-Output: "100"
+Input: prices = [3,2,1,4]
+Output: 7
+Explanation: There are 7 smooth descent periods:
+[3], [2], [1], [4], [3,2], [2,1], and [3,2,1]
+Note that a period with one day is a smooth descent period by the definition.
 ```
 
-## 题意
-> ...
-
-## 题解
+**Example 2:**
 
-### 思路1
-> ...
-Number of Smooth Descent Periods of a Stock
-```go
 ```
+Input: prices = [8,6,7,7]
+Output: 4
+Explanation: There are 4 smooth descent periods: [8], [6], [7], and [7]
+Note that [8,6] is not a smooth descent period as 8 - 6 ≠ 1.
+```
+
+**Example 3:**
 
+```
+Input: prices = [1]
+Output: 1
+Explanation: There is 1 smooth descent period: [1]
+```
 
 ## 结语
 

leetcode/2101-2200/2110.Number-of-Smooth-Descent-Periods-of-a-Stock/Solution.go

@@ -1,5 +1,16 @@
 package Solution
 
-func Solution(x bool) bool {
-	return x
+func Solution(prices []int) int64 {
+	l := len(prices)
+	c := int64(1)
+	ans := c
+	for i := 1; i < l; i++ {
+		if prices[i] == prices[i-1]-1 {
+			c++
+		} else {
+			c = 1
+		}
+		ans += c
+	}
+	return ans
 }

leetcode/2101-2200/2110.Number-of-Smooth-Descent-Periods-of-a-Stock/Solution_test.go

@@ -10,12 +10,12 @@ func TestSolution(t *testing.T) {
 	//	测试用例
 	cases := []struct {
 		name   string
-		inputs bool
-		expect bool
+		inputs []int
+		expect int64
 	}{
-		{"TestCase", true, true},
-		{"TestCase", true, true},
-		{"TestCase", false, false},
+		{"TestCase1", []int{3, 2, 1, 4}, 7},
+		{"TestCase2", []int{8, 6, 7, 7}, 4},
+		{"TestCase3", []int{1}, 1},
 	}
 
 	//	开始测试
@@ -30,10 +30,10 @@ func TestSolution(t *testing.T) {
 	}
 }
 
-//	压力测试
+// 压力测试
 func BenchmarkSolution(b *testing.B) {
 }
 
-//	使用案列
+// 使用案列
 func ExampleSolution() {
 }