Lab 3: Experiment 4

Relational Expressions

In addition to the arithmetic operators, C++ provides a variety of other operators including six relational operators. A relational operator allows two values to be compared, and it produces a boolean value indicating their relationship. A boolean value is either `true` or `false` indicating if the claim or relationship is true or false.

 `==` equality, returns true if and only if its operands are equal `!=` inequality, returns true if and only if its operands are different `<` less-than, returns true if and only if its left operand is less-than its right operand `>` greater-than, returns true if and only if its left operand is greater-than its right operand `<=` less-than-or-equal-to, returns true if and only if its left operand is not greater than its right operand `>=` greater-than-or-equal-to, returns true if and only if its left operand is not less than its right operand

In C++, a boolean value is represented by the `bool` type, so these operators produce a `bool` value. They are called the relational operators because they are used to identify the relationship between two values.

Add a line to your program that prints out these boolean values:

```cout << "true is " << true << "\n"
<< "false is " << false << endl;```

Question #3.4.1: What does your program display for this output statement?

Depending on your compiler, you may actually get the boolean values `true` and `false` to print out as words on the screen. More likely, you will get integer values, probably `1` for `true` and `0` for `false`. In C++, `0` is taken to be false, and strictly speaking, any non-zero value is true (although most compilers like to use the value `1`). When reading and reporting the results of this experiment, translate any integers into `true` and `false`.

Modify your program so that it

• Reads in values for `i` and `j` from the keyboard.
• Prints the results of comparing `i` and `j` using each of the relational operators listed above.
Note: you will have to put parentheses around a relational expression in an output expression. (We'll see why this is necessary in another experiment.)

Question #3.4.2: Find values for `i` and `j` in each row to make the indicated relationship true:
Relationship `i` `j`
`i < j`
`i <= j`
`i == j`
`i != j`
`i >= j`
`i > j`