golang刷leetcode动态规划（1）最长回文子串

输入: "babad"
输出: "bab"
注意: "aba" 也是一个有效答案。

输入: "cbbd"
输出: "bb"

func longestPalindrome(s string) string {
    if s==""{
        return s
    }
    a := make([][]int, len(s))
  for i := 0; i < len(s); i++ {
    a[i] = make([]int, len(s))
    a[i][i] = 1
  }
    for i := 0; i < len(s)-1; i++ {
        if []byte(s)[i]== []byte(s)[i+1]{
           a[i][i+1] = 1
        }
  }

  for j :=1;j<len(s);j++{
    for i := j-1;i>=0;i-- {
            if []byte(s)[i] == []byte(s)[j] &&  a[i+1][j-1]==1{
          a[i][j]=1
      } 
    }
  }
    max:=0
    ii:=0
    jj:=0
    for i:=0;i<len(s);i++{
        for j:=i+1;j<len(s);j++{
            if a[i][j]==1 &&j-i>max{
                max=j-i
                ii=i
                jj=j
            }
        }
        
    }
  return string([]byte(s)[ii:jj+1])
}