comefrom: <qiyuangong>005_Longest_Palindromic_Substring_1.java
code: private int expandAroundCenter(String s, int left, int right) {
          int L = left, R = right;
          while (L >= 0 && R < s.length() && s.charAt(L) == s.charAt(R)) {
              L--;
              R++;
          }
          return R - L - 1;
      }
masked: private int sample_funcname ( String var_0 , int var_1 , int var_2 ) {
    int var_3 = var_1 , var_4 = var_2 ;
    while ( var_3 >= 0 && var_4 < var_0 . length ( ) && var_0 . charAt ( var_3 ) == var_0 . charAt ( var_4 ) ) {
      var_3 -- ;
      var_4 ++ ;
    }
    return var_4 - var_3 - 1 ;
  }
  