add sol

leetcode/leetcode75/Backtracking/17.LetterCombinationsOfAPhoneNumber/letterCombinationsOfAPhoneNumber.go

@@ -0,0 +1,32 @@
+package main
+
+import (
+	"fmt"
+)
+
+func letterCombinations(digits string) []string {
+	result := []string{}
+	if len(digits) == 0 {
+		return result
+	}
+
+	phoneMap := []string{"abc", "def", "ghi", "jkl", "mno", "pqrs", "tuv", "wxyz"}
+	result = append(result, "")
+	for _, v := range digits {
+		s := phoneMap[v-'2']
+		temp := []string{}
+		for _, i := range result {
+			for _, j := range s {
+				temp = append(temp, i+string(j))
+			}
+		}
+		result = temp
+	}
+
+	return result
+}
+
+func main() {
+	digits := "25"
+	fmt.Println(letterCombinations(digits))
+}