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In this video, we'll talk about logic errors and why they can happen.

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Logic errors, or errors or bugs in your code

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that cause your program to run incorrectly.

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Logic errors are mistakes made by a programmer.

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Sometimes the mistakes are careless of the time.

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Some mistakes are because the programmers have incomplete or incorrect information.

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Other times mistakes occur when one programmer modifies another programmer's code

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to fix or add something, and they introduce an error as they do this.

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There are many, many causes for logic errors.

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It doesn't matter what the cause is though, they need to be corrected.

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We need to test our code and debug it to find incorrect errors.

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Suppose we have a program that determines if a person can vote in an election

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and you must be 18 years old or older to vote.

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We haven't talked about if statements yet in this class.

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But they're very intuitive and I'm sure you'll follow this little piece of code.

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First, we test to see if the age is greater than 18.

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If it is, then we execute the code that's inside those curly braces.

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Do you see the error.

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It’s pretty easy to see it here because the code is isolated,

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and I told you there was an error.

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However, in reality, there's much more code typically involved.

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In this may just be a small part of a much larger program.

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The problem with this code is that the test conditions should be greater than

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or equal to 18 or greater than 17,

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either one will work.

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As it's written now, 18 year old would not be able to vote.

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We'll talk about testing throughout the course in the context of

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learning c++ and best practices.

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Well, that wraps up this section.

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Next, you can take the section quiz and attempt the challenge exercise and see how you do.

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I'm sure you'll do great. If you have any questions, please post them to the course forum.