Merge pull request #1046 from 0xff-dev/2290

Add solution and test-cases for problem 2290

leetcode/2201-2300/2290.Minimum-Obstacle-Removal-to-Reach-Corner/README.md

@@ -1,28 +1,36 @@
 # [2290.Minimum Obstacle Removal to Reach Corner][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 a **0-indexed** 2D integer array `grid` of size `m x n`. Each cell has one of two values:
+
+- `0` represents an **empty** cell,
+- `1` represents an **obstacle** that may be removed.
+
+You can move up, down, left, or right from and to an empty cell.
+
+Return the **minimum** number of **obstacles** to **remove** so you can move from the upper left corner `(0, 0)` to the lower right corner `(m - 1, n - 1)`.
 
-**Example 1:**
+**Example 1:**  
+
+![1](./1.png)
 
 ```
-Input: a = "11", b = "1"
-Output: "100"
+Input: grid = [[0,1,1],[1,1,0],[1,1,0]]
+Output: 2
+Explanation: We can remove the obstacles at (0, 1) and (0, 2) to create a path from (0, 0) to (2, 2).
+It can be shown that we need to remove at least 2 obstacles, so we return 2.
+Note that there may be other ways to remove 2 obstacles to create a path.
 ```
 
-## 题意
-> ...
+**Example 2:**  
 
-## 题解
+![2](./2.png)
 
-### 思路1
-> ...
-Minimum Obstacle Removal to Reach Corner
-```go
 ```
-
+Input: grid = [[0,1,0,0,0],[0,1,0,1,0],[0,0,0,1,0]]
+Output: 0
+Explanation: We can move from (0, 0) to (2, 4) without removing any obstacles, so we return 0.
+```
 
 ## 结语
 

leetcode/2201-2300/2290.Minimum-Obstacle-Removal-to-Reach-Corner/Solution.go

@@ -1,5 +1,61 @@
 package Solution
 
-func Solution(x bool) bool {
+import "container/heap"
+
+type heap2290 [][3]int
+
+func (h *heap2290) Len() int {
+	return len(*h)
+}
+
+func (h *heap2290) Swap(i, j int) {
+	(*h)[i], (*h)[j] = (*h)[j], (*h)[i]
+}
+
+func (h *heap2290) Less(i, j int) bool {
+	return (*h)[i][2] < (*h)[j][2]
+}
+
+func (h *heap2290) Push(x any) {
+	*h = append(*h, x.([3]int))
+}
+
+func (h *heap2290) Pop() any {
+	old := *h
+	l := len(old)
+	x := old[l-1]
+	*h = old[:l-1]
 	return x
 }
+
+var dirs2290 = [][2]int{
+	{0, 1}, {1, 0}, {-1, 0}, {0, -1},
+}
+
+func Solution(grid [][]int) int {
+	m, n := len(grid), len(grid[0])
+	h := heap2290{{0, 0, 0}}
+	v := map[[2]int]int{
+		[2]int{0, 0}: 0,
+	}
+	for h.Len() > 0 {
+		cur := heap.Pop(&h).([3]int)
+		if cur[0] == m-1 && cur[1] == n-1 {
+			return cur[2]
+		}
+		for _, dir := range dirs2290 {
+			nx, ny := cur[0]+dir[0], cur[1]+dir[1]
+			if !(nx >= 0 && nx < m && ny >= 0 && ny < n) {
+				continue
+			}
+			need := cur[2] + grid[nx][ny]
+			key := [2]int{nx, ny}
+			//key = [3]int{nx, ny, need}
+			if vv, ok := v[key]; !ok || vv > need {
+				heap.Push(&h, [3]int{nx, ny, need})
+				v[key] = need
+			}
+		}
+	}
+	return -1
+}

leetcode/2201-2300/2290.Minimum-Obstacle-Removal-to-Reach-Corner/Solution_test.go

@@ -10,12 +10,11 @@ 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", [][]int{{0, 1, 1}, {1, 1, 0}, {1, 1, 0}}, 2},
+		{"TestCase2", [][]int{{0, 1, 0, 0, 0}, {0, 1, 0, 1, 0}, {0, 0, 0, 1, 0}}, 0},
 	}
 
 	//	开始测试
@@ -30,10 +29,10 @@ 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() {
 }