56 lines
1.4 KiB
Go
56 lines
1.4 KiB
Go
|
/*
|
|||
|
|
* @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, "#")
|
|||
|
|
}
|