Input and Output Streams
Predefined precedence is low enough to allow arithmetic expressions to appear in output without using parenthesis, as in:
cout << "a + b * c is " << a + b * c << '\n';
The left shift operator with its conventional meaning can be used in anoutput statement, by surrounding it with parenthesis:
cout << " a left shift by 3 is " << (a << 3) << '\n';