Final answer:
The program calculates the values of variables a, b, c, and sum. The line a *= 2 * b + c; multiplies the value of a by 2 * b + c. The output statement prints the current values of a, b, c, and sum separated by tabs.
Step-by-step explanation:
The given program calculates the values of variables a, b, c, and sum.
The line a *= 2 * b + c; multiplies the value of a by 2 * b + c. Then, the output statement, cout << a << ' ' << b << ' ' << c << ' ' << sum << endl;, prints the current values of a, b, c, and sum separated by tabs.
The output of the program will depend on the initial values of a, b, and c.