@Contract(pure = true)
  public static int commonSuffixLength(@NotNull CharSequence s1, @NotNull CharSequence s2) {
    int s1Length = s1.length();
    int s2Length = s2.length();
    if (s1Length == 0 || s2Length == 0) return 0;
    int i;
    for (i = 0; i < s1Length && i < s2Length; i++) {
      if (s1.charAt(s1Length - i - 1) != s2.charAt(s2Length - i - 1)) {
        break;
      }
    }
    return i;
  }
@Contract(pure = true)
  public static int commonSuffixLength(@NotNull CharSequence s1, @NotNull CharSequence s2)