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What are undeclared and undefined variables?

Rahul Roi 335 16-Mar-2021

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Rahul Roi

Rahul Roi

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1 Answers

16-Mar-2021

The undeclared variables are those that do not exist in a program and are not declared. Whenever the program tries to read the value of an undeclared variable, then a runtime error is encountered.

The undefined-variables are those that are declared in the program but have not been given any value. Whenever the program tries to read the value of an undefined variable, an undefined value is returned.