feat(Go-Tool)：2021/03/14: 新增Manacher算法，求最长回文串

util/palindrome/Manacher.go

@@ -0,0 +1,55 @@
+/*
+ *  @Author : huangzj
+ *  @Time : 2021/3/13 21:58
+ *  @Description：
+ */
+
+package palindrome
+
+import "fmt"
+
+//返回字符串中最大回文的数量和回文字符串
+func Manacher(allString string) (int, string) {
+	maxMid := 0    //当前最大回文串中部下标
+	radiusPos := 0 //最大回文半径对应的右边的下标位置
+	result := generateString(allString)
+	point := make([]int, len(result)) //以j为中心的最长回文半径
+	maxLen := -1
+	var palindrome string
+
+	for i := 1; i < len(result); i++ {
+		j := 2*maxMid - i //与i下标对称的左边的下标
+		if i >= radiusPos {
+			point[i] = 1
+		} else if radiusPos-i > point[j] {
+			point[i] = point[j]
+		} else {
+			// point[j] >= radiusPos-i
+			point[i] = radiusPos - i
+		}
+		//从后面的位置继续开始找对应的字符
+		for (i-point[i] >= 0 && i+point[i] < len(result)) && result[i+point[i]] == result[i-point[i]] {
+			point[i]++
+		}
+		//更新最长回文串信息
+		if i+point[i] > radiusPos {
+			maxMid = i
+			radiusPos = i + point[i]
+		}
+		if maxLen < point[i]-1 && point[i]-1 > 1 {
+			maxLen = point[i] - 1
+			palindrome = allString[maxMid/2-maxLen/2 : radiusPos/2]
+		}
+	}
+
+	return maxLen, palindrome
+}
+
+//把字符串转换成特殊的字符串
+func generateString(allString string) string {
+	var result string
+	for i := range allString {
+		result = fmt.Sprintf("%s%s%c", result, "#", allString[i])
+	}
+	return fmt.Sprintf("%s%s", result, "#")
+}

util/palindrome/Manacher_test.go

@@ -0,0 +1,28 @@
+/*
+ *  @Author : huangzj
+ *  @Time : 2021/3/13 21:58
+ *  @Description：
+ */
+
+package palindrome
+
+import (
+	"fmt"
+	"testing"
+)
+
+func TestGenerateString(t *testing.T) {
+	fmt.Println(generateString("abcdef"))
+	fmt.Println(generateString("abc2342def"))
+	fmt.Println(generateString("abcdef3213"))
+	fmt.Println(generateString("abcderewrewr312f"))
+	fmt.Println(generateString("312312abcdef321e"))
+}
+
+func TestPalindrome(t *testing.T) {
+	fmt.Println(Manacher("abcabccbacba"))
+	fmt.Println(Manacher("mabcabccbacbammm"))
+	fmt.Println(Manacher("habcabccbacbammm"))
+	fmt.Println(Manacher("hmmmabcabccbacbammm"))
+	fmt.Println(Manacher("abcdefghij"))
+}