package main

import "fmt"

func main() {
	str := "aaa"
	fmt.Println(countSubstrings(str))
}

func countSubstrings(s string) int {
	/*滑窗遍历*/
	sum := 0
	n := len(s)
	if n == 0 {
		return 0
	}
	for count := 1; count <= n; count++ {
		for i := 0; i+count <= n; i++ {
			if IsPalindrome(s[i : i+count]) {
				sum++
			}
		}
	}
	return sum
}

func IsPalindrome(s string) bool {
	n := len(s)
	for i:= 0  ; i < n/2 ; i ++  {
		if s[i] != s[n-i-1] {
			return false
		}
	}
	return true
}