Boolean type

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"Hi, Amigo. Let me tell you about a new data type. The boolean. Variables of this type can take only two values: true and false."

"How do we use it?"

"This type is implicitly used in many places. Just as any addition operation produces a number, the result of any comparison is a boolean. Here are some examples:"

boolean m;

boolean m = false;

if (a > b)
    System.out.println(a);

boolean m = (a > b);
if (m)
    System.out.println(a);

boolean m = (a > b);
if (m == true)
    System.out.println(a);

boolean m = (a > b);
if (m)
    System.out.println(a);

"More examples:"

public boolean isALessThanB (int a, int b)
{
    if (a < b)
        return true;
    else
        return false;
}

public boolean isALessThanB (int a, int b)
{
   boolean m = (a < b);
    if (m)
        return true;
    else
        return false;
}

public boolean isALessThanB (int a, int b)
{
    boolean m = (a < b);
    return m;
}

public boolean isALessThanB (int a, int b)
{
    return a < b;
}

"What if I want to write 0<a<b?"

"Java doesn't have a comparison operator that takes three operands. So, you would need to do it like this: (0<a) AND (a<b)."

"Do I write the word AND?"

"Wait. I'll explain that. Java has three logical operators: AND, OR and NOT. You can use them to construct conditions of varying complexity. You can use these operators only with boolean expressions. So, you can't write (a+1) AND (3), but (a>1)AND (a<3) is OK."

"The NOT operator is unary: it affects only the expression to the right. It's more like a minus sign before a negative number rather than a multiplication sign between two numbers."

"You can perform various operations on boolean (logical) variables."

"Like what?"

"Let's take a look:"

"Could you give me more examples?"

"Sure:"

"Now, do some tasks."