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@@ -0,0 +1,64 @@
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+package main
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+
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+import "fmt"
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+
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+func main() {
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+ var s string
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+
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+ s = "a"
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+ fmt.Println(longestPalindrome(s))
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+
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+ s = "ab"
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+ fmt.Println(longestPalindrome(s))
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+
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+ s = "aba"
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+ fmt.Println(longestPalindrome(s))
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+
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+ s = "abab"
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+ fmt.Println(longestPalindrome(s))
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+
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+ s = "ababc"
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+ fmt.Println(longestPalindrome(s))
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+
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+ s = "babad"
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+ fmt.Println(longestPalindrome(s))
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+
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+ s = "cbbd"
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+ fmt.Println(longestPalindrome(s))
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+}
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+
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+// 双指针法
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+func longestPalindrome(s string) string {
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+ var palindromeStr string
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+ var cursorFront, cursorBack int
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+ for i := 0; i < len(s); i++ {
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+ cursorFront = i
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+ for j := len(s) - 1; j >= i; j-- {
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+ cursorBack = j
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+ if s[cursorFront] != s[cursorBack] {
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+ cursorBack--
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+ continue
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+ }
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+ isPalindrome := checkString(cursorFront, cursorBack, s)
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+ if !isPalindrome {
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+ continue
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+ }
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+ if cursorBack-cursorFront+1 > len(palindromeStr) {
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+ palindromeStr = s[cursorFront : cursorBack+1]
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+ break
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+ }
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+ }
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+ }
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+ return palindromeStr
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+}
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+
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+func checkString(min, max int, s string) bool {
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+ for min <= max {
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+ if s[min] != s[max] {
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+ return false
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+ }
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+ min++
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+ max--
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+ }
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+ return true
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+}
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