Merge pull request #1041 from 0xff-dev/1861

Add solution and test-cases for problem 1861

Author: 6boris

leetcode/1801-1900/1861.Rotating-the-Box/1.png

@@ -1,28 +1,57 @@
 # [1861.Rotating the Box][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 `m x n` matrix of characters `box` representing a side-view of a box. Each cell of the box is one of the following:
+
+- A stone `'#'`
+- A stationary obstacle `'*'`
+- Empty `'.'`
+
+The box is rotated **90 degrees clockwise**, causing some of the stones to fall due to gravity. Each stone falls down until it lands on an obstacle, another stone, or the bottom of the box. Gravity **does not** affect the obstacles' positions, and the inertia from the box's rotation **does not** affect the stones' horizontal positions.
+
+It is **guaranteed** that each stone in `box` rests on an obstacle, another stone, or the bottom of the box.
+
+Return an `n x m` matrix representing the box after the rotation described above.
+
+**Example 1:**  
 
-**Example 1:**
+![1](./1.png)
 
 ```
-Input: a = "11", b = "1"
-Output: "100"
+Input: box = [["#",".","#"]]
+Output: [["."],
+         ["#"],
+         ["#"]]
 ```
 
-## 题意
-> ...
+**Example 2:**  
 
-## 题解
+![2](./2.png)
 
-### 思路1
-> ...
-Rotating the Box
-```go
 ```
+Input: box = [["#",".","*","."],
+              ["#","#","*","."]]
+Output: [["#","."],
+         ["#","#"],
+         ["*","*"],
+         [".","."]]
+```
+
+**Example 3:**  
+
+![3](./3.png)
 
+```
+Input: box = [["#","#","*",".","*","."],
+              ["#","#","#","*",".","."],
+              ["#","#","#",".","#","."]]
+Output: [[".","#","#"],
+         [".","#","#"],
+         ["#","#","*"],
+         ["#","*","."],
+         ["#",".","*"],
+         ["#",".","."]]
+```
 
 ## 结语
 

leetcode/1801-1900/1861.Rotating-the-Box/2.png

@@ -1,5 +1,29 @@
 package Solution
 
-func Solution(x bool) bool {
-	return x
+func Solution(box [][]byte) [][]byte {
+	rows, cols := len(box), len(box[0])
+	for i := 0; i < rows; i++ {
+		for j := cols - 2; j >= 0; j-- {
+			if box[i][j] == '.' || box[i][j] == '*' {
+				continue
+			}
+			next := j + 1
+			for ; next < cols; next++ {
+				if box[i][next] == '#' || box[i][next] == '*' {
+					break
+				}
+			}
+			box[i][j] = '.'
+			box[i][next-1] = '#'
+		}
+	}
+	res := make([][]byte, cols)
+	for i := range cols {
+		res[i] = make([]byte, rows)
+		for j := 0; j < rows; j++ {
+			res[i][j] = box[rows-1-j][i]
+		}
+	}
+
+	return res
 }

leetcode/1801-1900/1861.Rotating-the-Box/3.png

@@ -10,12 +10,31 @@ func TestSolution(t *testing.T) {
 	//	测试用例
 	cases := []struct {
 		name   string
-		inputs bool
-		expect bool
+		inputs [][]byte
+		expect [][]byte
 	}{
-		{"TestCase", true, true},
-		{"TestCase", true, true},
-		{"TestCase", false, false},
+		{"TestCase1", [][]byte{{'#', '.', '#'}}, [][]byte{{'.'}, {'#'}, {'#'}}},
+		{"TestCase2", [][]byte{
+			{'#', '.', '*', '.'},
+			{'#', '#', '*', '.'},
+		}, [][]byte{
+			{'#', '.'},
+			{'#', '#'},
+			{'*', '*'},
+			{'.', '.'},
+		}},
+		{"TestCase3", [][]byte{
+			{'#', '#', '*', '.', '*', '.'},
+			{'#', '#', '#', '*', '.', '.'},
+			{'#', '#', '#', '.', '#', '.'},
+		}, [][]byte{
+			{'.', '#', '#'},
+			{'.', '#', '#'},
+			{'#', '#', '*'},
+			{'#', '*', '.'},
+			{'#', '.', '*'},
+			{'#', '.', '.'},
+		}},
 	}
 
 	//	开始测试
@@ -30,10 +49,10 @@ 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() {
 }