View Compilation Error

0_0_21853068_17355.cpp: In function 'int main()':
0_0_21853068_17355.cpp:9:48: error: unable to find string literal operator 'operator""s'
  for (char i = 'A'; i <= 'Z'; ++i) rule += i + "*|"s;
                                                ^
0_0_21853068_17355.cpp:10:47: error: unable to find string literal operator 'operator""s'
  for (char i = 'a'; i < 'z'; ++i) rule += i + "*|"s;
                                               ^
0_0_21853068_17355.cpp:11:10: error: unable to find string literal operator 'operator""s'
  rule += "z*)"s;
          ^