Huge pre-assigned values to variables

This is a discussion on Huge pre-assigned values to variables within the C++ Programming forums, part of the General Programming Boards category; Ok...When I declare a variable. For this case, lets say x, but it doesn't really matter. I call upon x ...

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    Huge pre-assigned values to variables

    Ok...When I declare a variable. For this case, lets say x, but it doesn't really matter. I call upon x and it is just a massive seven or more digit number. I haven't even set x to anything yet, so I'm pretty sure that its not supposed to do that and i'm afraid i might screw up my computer.

    Can anyone tell me what's going on?

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    Can anyone tell me what's going on?
    You are getting garbage values since you did not initialise those variables.
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    I get maybe two dozen requests for help with some sort of programming or design problem every day. Most have more sense than to send me hundreds of lines of code. If they do, I ask them to find the smallest example that exhibits the problem and send me that. Mostly, they then find the error themselves. "Finding the smallest program that demonstrates the error" is a powerful debugging tool.
    Look up a C++ Reference and learn How To Ask Questions The Smart Way

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    ok, I guess that makes sense. Just out of curiousity, where do these garbage values come from.

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    Whatever was in that memory space before. Whether it was from computer startup, a previous program, your program, or whatever.

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    Thanks to both of you for your help, I thought I might be messing up my computer or something.

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    Note also that the compiler MAY do things like "fill all stack-space" [which is where your variables are stored] to some constant value. Microsoft Visual Studio fills memory with a patterns such as 0xCCCCCCCC or 0xDDDDDDDDD. This makes it a bit easier to idenitfy a variable that hasn't been set to anything, rather than it containing some completely random value. [This only happens in debug mode - it also slows down the code, particularly if you have large arrays in local functions].

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