AndreyT this guy has a nice summary which coincides with my opinion: groups. Show 8 more comments. Yes, there is value in this as it properly expresses the semantics you wish. Steve Townsend Steve Townsend You don't need C-style casts to cast away unsignedness. It's a simple static cast. It does two things: 1 It gives you double the range for your unsigned values values. It's not really a sign bit.
The statement "0 for positive" is correct; "0 means positive" is not what he said. In practice, using unsigned does double the range of values available. Potatoswatter I was being needlessly pedantic. When the "sign bit" is zero, the integer itself might be zero, which is neither positive or negative. Jeremy Friesner Jeremy Friesner However in the second case, you will not catch the error, but you will work with another "random" positive index that resulted from the unsigned-wrap around behavior.
That's much worse. Johannes: I don't see that. If idx was negative, it will be changed into a very large unsigned number over two billion for bit int s. Assuming arrayLength is a vaguely reasonable number, the second case will catch the error. David Well it's a principal problem of that thinking, not necessarily a problem in this particular case.
What if instead of idx you have len and there is no upper limit? Applying the principal applied in this answer means that you don't do any check anymore, and then you operate on that large length. No good. What if idx is 0!? Johannes Schaub - litb Johannes Schaub - litb k gold badges silver badges bronze badges. Many if not most compilers are able to warn on signed-to-unsigned conversions. This once saved my butt.
Konrad My point is that using unsigned will make the function unable to catch the error because the parameter in the function is always positive by definition.
The compiler can't warn you in all cases and sometimes just casting to unsigned on the call-side just to get rid of a warning will not fix any bug - instead a negative value will silently wrap around.
This will catch numbers that were originally negative as well. Therefor, you throw away half the unsigned range to detect negative value as positive values of the higher half. That's just completely backwards. Do it right and detect negative values when they are negative. Show 5 more comments. Evan Teran Evan Teran This rect example is nice.
Consider: In the above case, if r. When and by whom was "Declaration of Indian Rights" prepared? What was its significance? Write the units of van der waals constants 'a' and 'b',- what are the significances of 'a' and 'b'?
Significant wetlands of India are declared as. What does the cell constant mean and how is it determined? What is its significance in measuring the Write the significance of Vanderwaal's constants. Feedback will be sent to Microsoft: By pressing the submit button, your feedback will be used to improve Microsoft products and services.
Privacy policy. Skip to main content. This browser is no longer supported. Download Microsoft Edge More info. A character literal can be a plain character e. String literals or constants are enclosed in double quotes "". A string contains characters that are similar to character literals: plain characters, escape sequences, and universal characters. You can break a long line into multiple lines using string literals and separating them using white spaces.
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