Merge pull request #1258 from 0xff-dev/868

Add solution and test-cases for problem 868

Author: 6boris

leetcode/801-900/0868.Binary-Gap/README.md

@@ -1,28 +1,38 @@
 # [868.Binary Gap][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
+Given a positive integer `n`, find and return the **longest distance** between any two **adjacent** `1`'s in the binary representation of `n`. If there are no two adjacent `1`'s, return `0`.
+
+Two `1`'s are **adjacent** if there are only `0`'s separating them (possibly no `0`'s). The **distance** between two `1`'s is the absolute difference between their bit positions. For example, the two `1`'s in `"1001"` have a distance of 3.
 
 **Example 1:**
 
 ```
-Input: a = "11", b = "1"
-Output: "100"
+Input: n = 22
+Output: 2
+Explanation: 22 in binary is "10110".
+The first adjacent pair of 1's is "10110" with a distance of 2.
+The second adjacent pair of 1's is "10110" with a distance of 1.
+The answer is the largest of these two distances, which is 2.
+Note that "10110" is not a valid pair since there is a 1 separating the two 1's underlined.
 ```
 
-## 题意
-> ...
+**Example 2:**
 
-## 题解
-
-### 思路1
-> ...
-Binary Gap
-```go
+```
+Input: n = 8
+Output: 0
+Explanation: 8 in binary is "1000".
+There are not any adjacent pairs of 1's in the binary representation of 8, so we return 0.
 ```
 
+**Example 3:**
+
+```
+Input: n = 5
+Output: 2
+Explanation: 5 in binary is "101".
+```
 
 ## 结语
 

leetcode/801-900/0868.Binary-Gap/Solution.go

@@ -1,5 +1,21 @@
 package Solution
 
-func Solution(x bool) bool {
-	return x
+func Solution(n int) int {
+	ans, count := 0, 0
+	first := true
+	for ; n > 0; n >>= 1 {
+		if n&1 == 0 {
+			if !first {
+				count++
+			}
+			continue
+		}
+		if first {
+			first = false
+		} else {
+			ans = max(ans, count)
+		}
+		count = 1
+	}
+	return ans
 }

leetcode/801-900/0868.Binary-Gap/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 int
 	}{
-		{"TestCase", true, true},
-		{"TestCase", true, true},
-		{"TestCase", false, false},
+		{"TestCase1", 22, 2},
+		{"TestCase2", 8, 0},
+		{"TestCase3", 5, 2},
 	}
 
 	//	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() {
 }