We cannot use if statement it has o be done using switch only

When you write a "boolean statement" (i.e.: the contents of an "if" statement) outside of an "if" statement, it returns either true or false.

Your boolean statement is as follows:

Code:

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(num < 0)

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This can become the target of your switch like so:

Code:

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switch(num < 0) {
case true:
    alert('NUMBER IS NEGATIVE');
break
case false:
    alert('NUMBER IS POSITIVE OR ZERO');
break
}

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