Add solution and test-cases for problem 1138

leetcode/1101-1200/1138.Alphabet-Board-Path/README.md

@@ -1,28 +1,37 @@
 # [1138.Alphabet Board Path][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
+On an alphabet board, we start at position `(0, 0)`, corresponding to character `board[0][0]`.
+
+Here, `board = ["abcde", "fghij", "klmno", "pqrst", "uvwxy", "z"]`, as shown in the diagram below.
+
+![1](./1.png)
+
+We may make the following moves:
+
+- `'U'` moves our position up one row, if the position exists on the board;
+- `'D'` moves our position down one row, if the position exists on the board;
+- `'L'` moves our position left one column, if the position exists on the board;
+- `'R'` moves our position right one column, if the position exists on the board;
+- `'!'` adds the character `board[r][c]` at our current position `(r, c)` to the answer.
+
+(Here, the only positions that exist on the board are positions with letters on them.)
+
+Return a sequence of moves that makes our answer equal to `target` in the minimum number of moves.  You may return any path that does so.
 
 **Example 1:**
 
 ```
-Input: a = "11", b = "1"
-Output: "100"
+Input: target = "leet"
+Output: "DDR!UURRR!!DDD!"
 ```
 
-## 题意
-> ...
-
-## 题解
+**Example 2:**
 
-### 思路1
-> ...
-Alphabet Board Path
-```go
 ```
-
+Input: target = "code"
+Output: "RR!DDRR!UUL!R!"
+```
 
 ## 结语
 

leetcode/1101-1200/1138.Alphabet-Board-Path/Solution.go

@@ -1,5 +1,68 @@
 package Solution
 
-func Solution(x bool) bool {
-	return x
+import "strings"
+
+func Solution(target string) string {
+	pos := [26][2]int{
+		{0, 0}, {0, 1}, {0, 2}, {0, 3}, {0, 4},
+		{1, 0}, {1, 1}, {1, 2}, {1, 3}, {1, 4},
+		{2, 0}, {2, 1}, {2, 2}, {2, 3}, {2, 4},
+		{3, 0}, {3, 1}, {3, 2}, {3, 3}, {3, 4},
+		{4, 0}, {4, 1}, {4, 2}, {4, 3}, {4, 4},
+		{5, 0},
+	}
+	buf := strings.Builder{}
+	x, y := 0, 0
+	for _, b := range target {
+		bp := pos[b-'a']
+		if bp[0] == x && bp[1] == y {
+			buf.WriteByte('!')
+			continue
+		}
+		dx, dy := bp[0]-x, bp[1]-y
+		sx, sy := x, y
+		x, y = bp[0], bp[1]
+		if sx == 5 && sy == 0 {
+			if dx < 0 {
+				for ; dx < 0; dx++ {
+					buf.WriteByte('U')
+				}
+			} else {
+				for ; dx > 0; dx-- {
+					buf.WriteByte('D')
+				}
+			}
+			if dy < 0 {
+				for ; dy < 0; dy++ {
+					buf.WriteByte('L')
+				}
+			} else {
+				for ; dy > 0; dy-- {
+					buf.WriteByte('R')
+				}
+			}
+			buf.WriteByte('!')
+			continue
+		}
+		if dy < 0 {
+			for ; dy < 0; dy++ {
+				buf.WriteByte('L')
+			}
+		} else {
+			for ; dy > 0; dy-- {
+				buf.WriteByte('R')
+			}
+		}
+		if dx < 0 {
+			for ; dx < 0; dx++ {
+				buf.WriteByte('U')
+			}
+		} else {
+			for ; dx > 0; dx-- {
+				buf.WriteByte('D')
+			}
+		}
+		buf.WriteByte('!')
+	}
+	return buf.String()
 }

leetcode/1101-1200/1138.Alphabet-Board-Path/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 string
+		expect string
 	}{
-		{"TestCase", true, true},
-		{"TestCase", true, true},
-		{"TestCase", false, false},
+		{"TestCase1", "leet", "RDD!RRRUU!!DDD!"},
+		{"TestCase2", "code", "RR!RRDD!LUU!R!"},
 	}
 
 	//	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() {
 }