Chapter 3, Problem 37CP

Given: The following conditional expressions:

ï‚· score = x > 10 ? 3 * scale : 4 * scale;

ï‚· tax= income> 10000 ? income * 0.2 : income * 0.17 + 1000;

ï‚· cout <<(number % 3== 0 ? i : j)<

To find: The statements after the following conditional expressions that have been rewritten using if-else statements.

ï‚· score = x > 10 ? 3 * scale : 4 * scale;

ï‚· tax= income> 10000 ? income * 0.2 : income * 0.17 + 1000;

ï‚· cout <<(number % 3== 0 ? i : j)<

Solution:

In C++ programming, the symbol, “?� and “:�, can appear together to form a conditional expression. The conditional expression evaluates the expression based on the condition. Conditional expressions do not include an explicit if. The syntax is as follows.

boolean-expression ? expressionA : expressionB;

The result of this conditional expression will be expressionA if the Boolean expression gives true, else the final outcome will be expressionB.

ï‚· Using the if-else statement, the conditional expression is given below.

score = x > 10 ? 3 * scale : 4 * scale;

can be written as -

//if statement to check x is greater than 10

if ( x>10)

{

//multiply scale by 3 and assign to score

score=(3*scale);

}

//x is not greater than 10

else

{

//multiply scale by 4 and assign to score

score=(4*scale);

}

The above if else statements check for the value of x and assign value to score according to it.

If x is less than 10, then the score will be equal to scale multiplied by 3, else the score will be equal to scale multiplied by 4...