Discussion

The expression (a + b) * (c - d) is translated into three address code with one operator per instruction. How many instructions are produced?

Answer: B

With one operator per instruction, the instruction count equals the operator count. The expression \( (a+b)*(c-d) \) contains three operators, so \[ n = 3 \] namely \( t_1 = a + b \), \( t_2 = c - d \), and \( t_3 = t_1 * t_2 \). Three temporaries are introduced, the last holding the value of the whole expression.