优先级 操作符 结合性
1 :: 左
2 . -> [] () 左
3 ++ -- ~ ! - + & * () sizeof new delete castname_cast
4 .* ->* 左
5 * / % 左
6 + - 左
7 << >> 左
8 < <= > >= 左
9 == != 左
10 & 左
11 ^ 左
12 | 左
13 && 左
14 || 左
15 ?: 右
16 = *= /= %= += -= <<= >>= &= |= ^= 右
17 throw 左
18 , 左
