Question

The Pitfall section entitled "Leading Zeros in Number Constants" suggests that you write a short program to test whether a leading 0 will cause your compiler to interpret input numbers as base-eight numerals. Write such a program.

Short answer

Answer: Yes, compilers typically interpret numbers with leading zeros as base-eight (octal) numerals. For example, in C++, the expression `int testNumber = 010;` would actually assign the decimal value 8 to testNumber, because the leading 0 indicates that the number is in base-eight.

Step-by-step solution

Prepare the development environment

You will need a C++ compiler. Choose and install one, for example, GNU G++ or Microsoft Visual Studio.

Write the base-eight test program

Create a new C++ source file and write the following code: ```cpp #include int main() { int testNumber = 010; // Number with leading 0, should be interpreted as base-eight std::cout << "The value of testNumber is: " << testNumber << std::endl; return 0; } ``` This program initializes a testNumber variable with a leading 0, which we'd like to test if interpreted as base-eight. Then it prints the value of testNumber to the console.

Compile and run the program

Compile the C++ source file using a C++ compiler: ``` g++ baseEightTest.cpp -o baseEightTest ``` Run the compiled program: ``` ./baseEightTest ```

Observe the output

Check the output of the program. If the output is 8, it means the compiler has interpreted the number with a leading 0 as base-eight (as 1x8^1 = 8). Otherwise, the output will be 10 if interpreted as base-ten. This will help you understand how your compiler behaves with leading zeros in number constants, and whether it interprets them as base-eight numerals or not.